Every English verb has five different forms, but only two of the forms have a tense feature. The tensed forms are indicated with a morphosyntactic feature, either [+past] or [-past]. The form that a verb in the V-head position takes depends on what tense feature is in the T-head position, among other things.
|
bare
|
(non-tensed)
|
eat
|
walk
|
sing
|
take
|
|
[-past]
|
(tensed)
|
eats
|
walks
|
sings
|
takes
|
|
[+past]
|
(tensed)
|
ate
|
walked
|
sang
|
took
|
|
past participle
|
(non-tensed)
|
eaten
|
walked
|
sung
|
taken
|
|
present participle
|
(non-tensed)
|
eating
|
walking
|
singing
|
taking
|
But there are some quirks of English that can make things confusing:
Is it bare or [-past]?
For just about every verb, the [-past] form is recognizable in the 3rd-person-singular form (
she eats/walks/sings/takes
). The 1st & 2nd-person forms
(
I eat/walk/sing/take
and
You eat/walk/sing/take
) look just like the bare form (
eat/walk/sing/take
).
If you’re looking at a verb and can’t tell if it’s in the bare form or the
[-past] form, give it a 3rd-person subject and then look for the
–s
morpheme:
I
want
to
visit
Saskatoon.
(bare or [-past]? Can’t tell: they’re ambiguous)
She
wants
to
visit
Saskatoon.
(
wants
is [-past],
visit
is bare)
Is it [+past] or past participle?
For many English verbs, the [+past] form (
She
bought
a donut
) and the past participle form (
She has
bought
a donut
) are the same.
If you’re looking at a verb and can’t tell if it’s in the [+past] form or the past participle form, try replacing it with the verb
eat
:
She
bought
a donut after she had
walked
the dog.
( [+past] or past participle? Can’t tell: they’re ambiguous)
She
ate
a donut after she had
eaten
the dog.
(Silly, but grammatical)
The form
ate
is [+past], while
eaten
is past participle,
so we can conclude that, in that sentence,
bought
is [+past] while
walked
is the past participle)
What about auxiliaries?
The modal auxiliaries never change their form: they occupy the T-head position in their own right.
The non-modal auxiliaries, like main verbs, change their form depending on what tense feature is in the T-head position, among other things.
|
bare
|
(non-tensed)
|
be
|
have
|
do
|
|
[-past]
|
(tensed)
|
am/are/is
|
has
|
does
|
|
[+past]
|
(tensed)
|
was/were
|
had
|
did
|
|
past participle
|
(non-tensed)
|
been
|
had
|
done
|
|
present participle
|
(non-tensed)
|
being
|
having
|
doing
|