In Part 1, we answered the question why past tense verbs cannot follow sense words such as
hear. For example:
(1) We heard her crying. (not *cried)
That answer is inadequate because it fails to account for a sentence like (2):
(2) We heard John escaped.
In (2) we have the sense verb
heard just like in (1), so we might expect the past tense
escaped to be unacceptable. Yet
escaped is acceptable in (2) after the sense verb
heard.
Why, you may wonder.
Well, the answer lies in the clause after the sense verb. In sentence (2), this clause is
John escaped and in (1), it is
her crying. The former is a finite clause and the latter is a non-finite clause.
A finite clause contains a subject and a verb phrase that carries tense:
(3)
He lives here.
(4)
She jogged yesterday.
In (3) for example, the verb phrase
lives here contains the present tense verb
lives, so the clause (which is also the entire sentence) is finite.
We thus say
John escaped is finite because it contains a subject
John and a finite verb
escaped. We can test this in a number of ways. For instance, we can replace
John with a subject pronoun
he but not with an object pronoun
him:
(5) We heard he escaped.
(6) *We heard him escaped.
We can usually insert the conjunction
that before a finite clause:
(7) We heard that John escaped.
A non-finite clause, on the other hand, usually does not have an overt subject and carries no tense markers:
(8) She loves
to sing.
(9) They made
him run.
(10) He dreads
getting up so early.
In (8) for example, the clause
to sing does not have an overt subject and is not marked for tense, so it is non-finite.
If a clause is non-finite, we can neither use a subject pronoun nor insert the conjunction
that:
(11) *We heard she crying.
(12) *We heard that her crying.
The analysis above applies to causative verbs as well:
(13) They made him wait.
The clause
him wait is non-finite, because we can't replace
him with
he and neither can we insert the conjunction
that:
(14) *They made he wait.
(15) *They made that him wait.
Using the notion of finiteness, we can easily explain the tensed
swam in (16) and the non-tensed
swim in (17):
(16) We watched as they
swam.
(17) We watched them
swim.