What kind of clause is the words After grill hot?

The phrase "After grill hot" is not a clause. It's a prepositional phrase functioning as an adverbial phrase.

Here's why:

* Clause: A clause contains a subject and a verb. "After grill hot" has neither.

* Prepositional Phrase: It starts with a preposition ("after") and ends with a noun or pronoun ("grill hot").

* Adverbial Phrase: It modifies the verb (often implied) in a sentence. For example:

* "After the grill is hot, you can start cooking."

In this example, "After the grill is hot" modifies the implied verb "start" and tells us when the cooking begins.