A Survey of ASL tenses

A Survey of ASL Tenses

Karen Alkoby

DePaul University

School of Computer Science

Chicago, IL

kalkoby@shrike.depaul.edu

Abstract

This paper examines tenses in American Sign Language (ASL), which will be useful for the ASL

Translation project. In the past, researchers believed that ASL used only Time Adverbials to

indicate time. However, new evidence indicates that ASL marks tense grammatically as well. In

order to properly analyze ASL tense structure, Aarons, Bahan, Kegal and Neidle identified the

Lexical Tense Marker and proposed a notion called "Tense Phrase", which is a very important

concept of the ASL syntax. This paper will discuss this Tense Phrase in great detail along with

Time Indicator, Time Adverbial and Lexical Tense Marker.

1. Introduction

As a native signer of American Sign Language (ASL), I find that I must often verify the tense of

sentences with a sign language interpreter because improper use of the ASL tense can lead to

severe miscommunication. For example, in Legal Ramification of an Incorrect Analysis of Tense

in ASL [

], a deaf plaintiff misunderstood when he was asked “Did you understand when you

were signing the paper at [Company A] that you were borrowing money and agreeing to pay it

back?” The plaintiff responded, “Yes” because he thought the question asked if he understood at

the present time when he was questioned, but was not aware that the question asked if he

understood at the time when he was signing the paper. In order to synthesize ASL tense structure

properly by using the notions, Tense Phrase and/or Adverbial Time [i] are essential concepts.

This paper will discuss these concepts: Tense Phrase, Time Indicator, Time Adverbial and

Lexical Tense Marker.

2. Notational Convention

This section describes the notations for the signs, which will be used in this paper [iii]. Most of

these notations are widely accepted for transcribing ASL is shown in the next page.

SYMBOL EXAMPLE EXPLANATION

NOT-YET

S-U-E

When more than one English word is needed to gloss an

ASL sign, The English words are separated by hyphenation.

In addition, when there is hyphenation between all letters

such as S-U-E, this indicates a fingerspelling.

#WILL

When this symbol is written before a gloss, it indicates the

sign is a fingerspelled loan sign. Fingerspelled loan sign do

not spell out every letter in a gloss. For example, the

#WILL sign spells as W-L instead of spelling out every

letter for “W-I-L-L”.

* I-GIVE-YOU

When this symbol is written before a sentence in an

example, it indicates the syntax is incorrect.

_____neg______

NOT

This indicates a negation non-manual signal. This includes

a side-to-side headshake, frequently accompanied by a

frown, and sometimes a brow squint, a wrinkling of the nose

and/or raised upper lip

_____top______

S-U-E

This indicates a topic marker with a non-manual signal in

which the head tilts back as the eyebrows raise. ASL is a

topic-prone language. The strategy of topicalization is to

place the main focus of a thought at the beginning of the

sentence.

3. Computational Linguistics

Translating English to American Sign Language draws upon the specialty in Artificial

Intelligence (AI) called Computational Linguistics. Computational linguistics involves computer

representation of human language. Problems in Computational Linguistic fall into two areas:

conceptual problems and technical problems.

Conceptual problems pose questions in order to gain a better understanding of how humans

communicate by using natural language. This area is shared with theoretical linguistics and

psycholinguistics. Technical problems include building intelligent computer systems, such as

natural language interfaces to databases, automatic machine-translation system, text analysis, and

animations.

This paper surveys and analyzes the conceptual problem of ASL tenses. ASL tense is one of

many components required for a complete ASL syntax. As in all machine translation systems, it

is necessary to have a deep understanding of the syntax of any target language. Until now, no

one has investigated the syntax of ASL in the context of creating a machine translator. To survey

and identify the conceptual problem in ASL correctly is an essential part for successful

completion of a machine translator project.

4. Time Indicator

The time indicator is one of the features that makes language unique as a communication system

in that its users are not limited to talking about people, events, or things that are immediately

visible or presently occurring [

]. In English for example, we use time indicator morphemes to

express tense. For example, we add “s” to indicate present third person, and “ed” bound

morphemes to indicate past tense. Unlike English, verbs in ASL do not use bound time indicator

morphemes.

Time indicators in ASL are often called time signs. FINISH, WILL, and #WILL are examples

of ASL time signs. The FINISH sign is used to indicate past tense or actions that have been

completed, while the WILL and #WILL signs are often used to indicate future tense. ASL also

uses present time signs such as NOW and TODAY. Although ASL has time indicator signs, they

are not used in every sentence because they are considering redundant. Here is a short example

of a sequence of English sentences.

Yesterday, I went to the class. I sat on a good chair. I listened to the lecture.

Every sentence above contains a past tense morpheme. A word-for-word conversion would

result in a past time indicator in every sentence, which adds too much redundancy and is

considered ungrammatical in ASL.

* YESTERDAY I FINISH GO CLASS. I FINISH SIT GOOD CHAIR. I FINISH LISTEN LECTURE.

The correct syntax in ASL for these sentences would be as follows:

YESTERDAY I GO CLASS. SIT GOOD CHAIR. LISTEN LECTURE.

If a time is specified in a sentence, then all the events a signer describes are understood as

occurring at that time [

iii

]. This holds true not only for that sentence but also for all subsequent

sentences until a new time is specified. Therefore, an English-to-ASL translator system must be

robust enough to keep track of the time for events and identify any changes including- present,

near past, far past, near future and far future. This will remove unnecessary time indicator signs

from sentences when converting from English to ASL. A database also will need to have a field

to identify the time attribute for independent lexical time indicators such as TOMORROW,

TODAY and FROM-NOW-ON signs. The translating program must also determine correct

tenses for embedded sentences. For example in the sentence, “Yesterday she told me that she

would call you tomorrow”, the time indicator in the main clause introduces the tense for the

whole sentence, and the embedded clause remains as a tenseless complement. Table 1 shows

some examples of ASL time signs, grouped by the tenses, which are familiar in English.

Present Past Future Recent

NOW ONE-DAY-PAST FEW-DAY-FUTURE RECENTLY

TODAY FEW-DAY-PAST WILL

UP-TILL-NOW PAST FUTURE

EARLY-MORNING LONG-TIME-AGO DISTANT-FUTURE

ONCE-UPON-A-TIME ONE-YEAR-FUTURE

Table 1: ASL Time Signs

5. Lexical Tense Markers and Time Adverbials

There are two kinds of time signs in ASL: Lexical Tense Markers and Time Adverbials. Lexical

Tense Markers are lexically independent time signs, whereas Time Adverbials are time signs that

function as adverbs. Most Lexical Tense Markers have corresponding Time Adverbials, which

are morphologically related [i]. However not all time signs have two categories. For example,

the #EX sign (for ex: ex-husband/ex-worker) is known and has been studied for non-related

Adverbial Time. This means #EX sign can’t be used as Time Adverbials and it will be used as

Lexical Tense Marker only. In ASL syntax, Time Adverbials can appear almost order-

independently in a sentence, whereas Lexical Tense Markers can only appear at more restricted

positions. There is clear evidence that Lexical Tense Markers and Time Adverbials are distinct. I

will discuss Lexical Tense Markers and Time Adverbials in detail in the next sections.

5.1 Lexical Tense Marker

When -TNS is added to the right side of a gloss, it indicates the gloss symbol is a Lexical Tense

Marker. The WILL sign has two classifications: FUTURE-ADV or FUTURE-TNS. FUTURE-

ADV is the future adverbial, while FUTURE-TNS is the future lexical tense marker. Table 2

shows some examples of ASL Lexical Tense Markers.

FUTURE-TNS

A 5 handshape moving in an arcing motion from the present line of

the shoulder to the future timeline.

PAST-TNS

Bent B-handshape tapping (or moving toward) the shoulder.

RECENT-PAST-TNS

Articulated either like the PAST-TNS but with more restrained

movement, or else like the sign RECENT; both articulation co-occur

with cs (cheek-to-shoulder) face (the facial expression

___CS

, also

found with the adverbial marker ‘recently’).

UP-TO-NOW

(often glossed SINCE) Articulated with two index fingers, bent at the

first knuckle, palm downward, finger points contacting upper shoulder

and moving in an arcing motion to palm-up orientation at about chest

height in front of the body.

IMMEDIATE-PRESENT-TNS

Similar to the glossed sign for NOW but it is closer to the body. It is

co-occurring with a non-manual marker: teeth clenched, lips

stretched, mouth corners pulled downward.

FORMERLY-TNS

A 5 handshape moving in a small circular motion with thumb side

brushing against collar bone

#EX-TNS

Identical articulation to that of fingerspelled loan sign corresponding

to ‘ex-husband/wife;

Table 2: The Lexical Tense Markers [ i]

5.2 Time Adverbials

ASL expresses information about time with a specific set of signs that are produced in relation to

what is called a time line, illustrated on the Figure 1 [iii]. The time signs have a relative location

on the time line, which agrees with their meaning. In addition to the timeline, the height defines

the coordinate system of the sign location. In some cases, height distinguishes tense markers

from time adverbials.

Figure 1: “Time line” [iii]

The timeline is indicated on the illustration above as starting from Far past, Past, Near Past,

Present, Near Future, and Far future respectively with the vertical lines from left to right.

According to Cogen [

] , the articulation of time adverbials has been described relative to an

imaginary time line that divides the signing space, with the signer’s body representing the plane

of the present, the space in front of the signer representing the future, and the space behind

representing the past. The signs for such adverbials are articulated with a movement in either a

forward or a backward direction corresponding to future or past, respectively. The path of these

signs extends further in space either forward or backward to express greater distance in time

either in the future or the past.

The two future time indicators in Table 3 use height as well as the time line in their movement.

The WILL sign can be expressed as a lexical tense marker (FUTURE-TNS) or as a time

adverbial (FUTURE-ADV). In notation, the time adverbials are indicted with –ADV to the right

Height

Location

of the gloss. The FUTURE-TNS has a fixed form using the WILL sign. The FUTURE-ADV has

various forms that use the WILL sign depending on the location timeline.

SIGN GLOSS From

Location

From

Height

FUTURE-TNS

“Present”

timeline

FIXED (A few inches away

forward from the face)

Cheek Chin

FUTURE-ADV

“Present”

timeline

Variable depending on the

semantic and according to

the timeline

Forehead Cheek

Table 3:Future Time Signs

The FUTURE-TNS is a lexical tense marker and always has a fixed path length. The fixed path

length for the FUTURE-TNS starts moving from the location of present to somewhere between

Near Future and Future on the time line with B-handshape oriented palm-sideward in forward

extension.

1) [FUTURE-TNS] I GO SCHOOL.

‘I will go to the school.’

2) [FUTURE-ADV] I GO SCHOOL.

‘In the near future, I will go to the school.’

3) [FUTURE-ADV] I GO UNIVERSITY.

‘In the far future, I will go to the University.’

Unlike lexical time markers, the time adverbials have no fixed path length. The length of the path

is dependent on semantics. In (2) above, FUTURE-ADV starts moving from the location of

present to the near future space, whereas in (3), the FUTURE-ADV sign starts moving from the

location of present to the far future space.

SIGN GLOSS From

Location

From

Height

PAST-TNS

“Present”

timeline

Fixed (near the shoulder) Cheek Shoulder

PAST-ADV

“Present”

timeline

Variable depending on the

semantic and according to

timeline

Cheek Shoulder

Table 4:Past Time Signs

4) [PAST-ADV] I STUDENT GALLAUDET.

‘In the past, I was a student at Gallaudet.’

5) [PAST-TNS] I STUDENT GALLAUDET.

‘I was a student at Gallaudet.’

Another example of time signs for the past time indicator is given in Table 4, which lists the

movement from the location to the next location and the height level. It is similar to the future

time signs. The only difference is that the signing movements are in the backward direction.

Finally, in the next sections discuss on how and why the lexical tense markers and time

adverbials are distinct.

6. Tense Phrase

Tense Phrase is a notion proposed by Aarons, Bahan, Kegal and Neidle [i]. It is a phrase (or

clause), which has a tense indicator. A tense phrase has a hierarchical structure and is depicted

by a tree which is rooted by the “Tense Phrase” node and which has the “Tense” node, as shown

in Figure 2.

Either modals or lexical tense markers may appear in the Tense node [i]. Modals in ASL include

CAN, MUST, SHOULD and HAVE-TO. Modals and lexical tense markers may occur in no

other syntactic position. The Tense node in a tense phrase is found between the subject Noun

Phrase and the Negation Phrase (if the phrase is a negation) or the Aspect Phrase, which contains

a Verb Phrase. The Tense node is the head of the ASL tense clause structure, indicated by T’ in

Figure 2 . Negation such as NEVER and NOT and the adverbials may appear to the right of

Tense, followed by the Verb Phrase. This structure applies to almost all sentence types in ASL,

such as Yes/No question, WH-question, declarative statements and etc. The non-manual

signals, which include facial expression and/or body movement, can easily classify the sentence

type.

Tense Phrase

Noun T’

Phrase

Tense Negation Phrase

Negation Aspect Phrase

Aspect Verb Phrase

Figure 2: ASL Tense Clausal Structure [partially from i]

The comparison between the lexical tense markers and time adverbials in terms of placement in

the ASL syntax list as follows [i]:

LEXICAL TENSE MARKERS TIME ADVERBIALS

Necessarily occur to the right of the Noun Phrase May occur in several positions in the sentence but not in the

position occupied by modals and tense markers

Necessarily occur to the left of negation Do not appear in the position immediately to the left of

negation

May contract with negation May not contract with negation

Necessarily occur to the left of lexical aspect markers

Table 5: Comparison of Lexical Tense Marker and Time Adverbials [partially from i]

A modal or a lexical tense marker occurs only under the Tense node. It has been shown that

lexical tense marker patterns with modals are therefore distinguishable from time adverbials in

terms of the syntactic position in which they occur [i]

6) TOMORROW S-U-E BUY HOUSE.

‘Sue will buy a house tomorrow’.

7) S-U-E BUY HOUSE TOMORROW.

‘Sue will buy a house tomorrow’.

8) S-U-E TOMORROW CAN BUY HOUSE.

‘Sue can buy a house tomorrow’

---------------TOP------

9) TOMORROW S-U-E BUY HOUSE.

‘Sue will buy a house tomorrow’

10) * S-U-E BUY TOMORROW HOUSE.

‘Sue will buy a car tomorrow.”

A Time adverbial such as TOMORROW may appear in any of the following positions: in the

beginning of the ASL clause shown in (6), or at the end of the ASL clause shown in (7), or

between the subject of Noun Phrase and Tense as shown in (8). Note that a modal such as CAN

could co-occur with time adverbials and is acceptable in any positions where a time adverbial can

occur. Also the time adverbial can appear in the topic position at the beginning of the sentence as

shown in (9). However, the time adverbial cannot appear between a verb and its object as shown

in (10). Note that a lexical tense marker may appear at other positions in a sentence. However,

this issue is outside the scope of this paper and will not discussed.

Whenever a negation occurs in the syntax, it is ungrammatical to use time adverbials. Using the

lexical tense marker is a proper way to deal with it. A negation such as NEVER and NOT may

appear to the right of Tense. The Tense Phrase is between the Noun Phrase of the surface

subject and Verb Phrase. In the (11), (12) and (14), (15), the FUTURE-ADV must be a lexical

tense marker and it is placed under a Tense node. Due to the negation statement, the possibility

for tense marker placement is restricted. See examples (11) through (15).

______

NEG___________

11) S-U-E FUTURE-TNS NOT BUY HOUSE OR

______

NEG___________

S-U-E NOT BUY HOUSE FUTURE-TNS

‘Sue will not buy the house ’

______

NEG___________

12) FUTURE-TNS S-U-E NOT BUY HOUSE

‘Sue will not buy the house ’

______

NEG___________

13) * S-U-E FUTURE-ADV NOT BUY HOUSE

‘Sue in the future (will) not buy a house’.

______

NEG___________

14) S-U-E UP-TO-NOW-TNS NOT BUY HOUSE

‘Sue has not bought a house up to now’

______

NEG___________

15) S-U-E PAST-TNS NOT BUY HOUSE

‘Sue did not buy a house’.

The lexical tense marker does not occur in infinitival complements [i]. For example, sentences

(16) and (17) have an infinitival complement clause “to buy” for the verbs ”want” or ”prefer” .

ASL does not have an overt marker corresponding and to the infinitive (like “to”) in English.

Modals also cannot occur in infinitival complements as shown in (18) and (19).

16) S-U-E WANT BUY HOUSE.

‘Sue wants to buy a house.’

17) S-U-E PREFER BUY HOUSE NEXT-YEAR.

‘Sue prefers to buy a house next year.’

18) * S-U-E PREFER FUTURE-TNS BUY HOUSE.

‘Sue prefers will buy a house.’

19) * S-U-E- PREFER CAN BUY

‘Sue prefers to be able to buy

7. Time Non-Manual signals

In addition to time indicators, non-manual signals play an important role in specifying tense in

ASL. Non-manual signs in ASL incorporate facial expressions and/or body movement. Without

it, a statement will be meaningless regardless of whether the syntax is in the proper order. To

demonstrate their importance, consider the fact that ASL does not use different syntax structure

for various sentence types. Instead, ASL relies on non-manual signals to convey the difference

between declarative, imperative and interrogative sentences. This paper focuses on non-manual

signal tense markers only.

Facial expression and other non-manual behaviors can indicate time in ASL [iii]. The notation

for non-manual signals uses an extended line over the section of a sentence where the non-

manual signals occur. Sometimes the non-manual signals can appear with verbs such as

“ARRIVE”. The various non-manual signals are summarized in Table 6 in the next page

Notation Description Non-manual signals Examples

__cs__

“closeness to the present time

space”.

It called as cheek-to-shoulder

Raising and moving the shoulder forward

and raising the cheek and side of mouth

toward that shoulder

VERY RECENTLY

JUST NOW

JUST ARRIVED

__intense

Awfully far away in time

space

Teeth clenched, lips stretched, and mouth

corners pulled downward and sideward

movement of the head

AWFULLY LONG

TIME AGO

AWFULLY FAR IN

THE FUTURE

_past_

This can be incorporated with

tense non-manual signals

without having to add a

lexical marker or time

adverbial sign

Upturn of the corner of mouth, as well as

slight backwards and sideward movement

of the head

BREAK

ARRIVE

__fut__

This could be incorporated

with e tense non-manual

signals without having to add

a lexical marker or time

adverbial sign

A slight forward head lean and a different

mouth position.

BREAK

ARRIVE

__immediate.pres

Immediately present marker Teeth clenched, lips stretched, and mouth

corners pulled downward

NOW

Table 6: Non-manual signals [i,iii]

8. Conclusion

The English to ASL translator system must be robust enough to keep track of the time for events

and identify any changes in time including references to present, near past, far past, near future

and far future. This system should be able to make a correct decision to address any tenseless

complements. Since the Tense Phrase is the head clause of the ASL syntax, the translator system

will likely start by resolving the ASL tense issues. This program would need to incorporate

pattern matching to replace words with the equivalent ASL gloss. For example consider the

sentence, “In the far future, I will go to the University”. The program should be able to convert

“In the far future” into FUTURE-ADV and set the path length from the present to the far future

timeline along with puffed-cheek non-manual signals. Then it should be able to delete the

redundant word “WILL”.

Often entire phrases in English can be replaced with one sign. (It would be a good idea to have a

separate table that uses the time sign to reduce the amount of time for searching the database).

This paper only examines and gives some guidelines on how to use ASL tense properly in term

of syntax positions and non-manual signals. Obviously, this translator program will make use of

a rule system to select a lexical tense marker or time adverbial. We currently have enough facts

from previous research to make it possible to develop some strategies for converting English

tenses into ASL tenses for use in the ASL Translator project. These strategies will be used as

essential conceptual information when developing implementation strategy for computer

representation of ASL tenses. As a next step This will be addressed as a technical problem in

computational linguistics.

BIBILOGRAPHY

Legal Ramifications of An Incorrect Analysis of Tense in ASL, James Shepard-Kegl, Carol Neidle, & Judy Kegl,

In: Journal of Interpretation, 1995, pg. 53-70

Linguistics of American Sign Language, 2

edition, Clayton Valli & Ceil Lucas, 1992, Gallaudet University Press

iii

American Sign Language, The Original Green Books, A Teacher’s Resource Text on Grammar and Culture,

Charlotee Baker-Shenk & Dennis Cokely, Gallaudet University Press, 1980

Cogen, C. (1977). On Three aspects of Time Expression in ASL. In L. Friedman (Ed.), On the other hand. New

York: Academic Press.