Verbs of senses (Part 2)

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.