He seems happy.
He seems to be happy.
In the first sentence, "happy" is the predicate adjective. What is going on in the second sentence? Does the infinitive with "happy" still function in the same manner, as a predicate adjective?
He seems happy.
He seems to be happy.
In the first sentence, "happy" is the predicate adjective. What is going on in the second sentence? Does the infinitive with "happy" still function in the same manner, as a predicate adjective?
Yes, “happy” is a predicative adjective in “He seems to be happy”.
In this sentence, "seems" is used as a catenative verb (a verb that forms a chain with another verb). The second verb can itself take its own complement, which it does in this case.
The second verb in this case is "to be", and "to be" can take a predicative adjective, such as "happy", as its complement. Compare “He is happy".
Despite the similarity in meaning, the sentence "He seems happy" isn't especially relevant from a grammatical point of view, because it involves a different, non-catenative use of "seem". For comparison, "seems" can also be used as a catenative verb in contexts where there is no predicative adjective, such as "He seems to like the movie" (where "the movie" is the direct object of "to like", which is the catenative complement of "seems").