A predicate adjective completes the meaning of the predicate verb and is therefore a complement ([§ 172, 3].)
Like the predicate nominative, the predicate adjective is common after copulative verbs and after certain transitive verbs in the passive voice ([§§ 172, 3]; [252]).
- John was angry.
- My knife is growing dull.
- The task seemed very easy.
- The report proved false in every particular.
- The boat was thought unsafe.
- The cover was made perfectly tight.
In some of these examples, the predicate adjective has a modifier. In the third, easy is modified by the adverb very; in the fourth, false is modified by the adverbial phrase in every particular; in the last, tight is modified by perfectly.
493. An adjective phrase may be used as a predicate adjective. Thus,—
- Richard was out of health. [Compare: Richard was ill.]
- Rachel seemed in a passion. [Compare: seemed angry.]
- This act is against my interests. [Compare: is harmful to me.]
The adjective phrase may consist of an infinitive with or without the preposition about ([§ 319]).
- I was about to speak.
- This house is to let.
- I am to sail to-morrow.