This is a phrase:
in the hat
This is not a phrase:
hat the in
This is a phrase (not a clause):
Rex the dog
This is a clause:
The easiest type of clause to identify has a stated subject and a predicate:
Rex [SUBJECT] || barked [PREDICATE].
Rex [SUBJECT] || barked at the cat [PREDICATE].
(“Barked” is the verb. “Barked at the cat” is the complete predicate. The predicate includes the verb.)
Rex the dog [SUBJECT] || barked at the cat [PREDICATE].
(“Rex the dog” is the complete subject. “Barked at the cat” is the complete predicate.)
A phrase does not have the subject-predicate structure of a clause:
on the boat
in the classroom
would have been
Note: In everyday language the term “phrase” refers to two or more “grammatically related” words. (“the big dog” not “dog big the”) Grammarians, however, also use the word “phrase” to apply to just one word because a single word can serve the same function as a phrase:
|Rex is barking.||is barking|
|Rex the neighbor dog barked.||Rex the neighbor dog|