"To boldly go where no man has gone before."
I phrase that begins with an infinitive: to fly, to walk, to vote, etc.
The infinitive phrase is "to join the circus" (an adverbial phrase).
The phrase "to be" is an infinitive verb phrase in English.
An infinitive phrase will start with the base form of a verb (e.g., to eat, to run) and function as a noun, adjective, or adverb. A prepositional phrase will begin with a preposition (e.g., in, on, at) followed by a noun or pronoun, and it functions as an adjective or adverb to describe a noun or verb.
It means Hi and goodbye
Since "area" is not a verb, "to area" cannot be an infinitive phrase, or even just an infinitive. "To area" could be a prepositional phrase but it does not appear to have any meaning by itself. One might say "to the area" but never simply "to area."
An infinitive phrase. An infinitive phrase is a noun phrase with an infinitive as its head. Unlike the other noun phrases, however, an infinitive phrase can also function as an adjective or an adverb.
"To run" is an infinitive because it is the base form of the verb without any tense or subject attached to it. Infinitives are commonly used after certain verbs or as subjects, complements, or objects in a sentence.
The infinitive phrase here is "to watch".
"To join the circus" is the infinitive phrase.
"To join the circus" is the infinitive phrase.
"To join the circus" is the infinitive phrase.
The infinitive phrase is "to join the circus" (an adverbial phrase).
An infinitive phrase will begin with an infinitive [to + simple form of the verb]. It will include objects and/or modifiers.
Infinitive
"to finish your test" is the infinitive phrase.
The infinitive phrase plays the role of an adverb in this sentence. It tells why you met at the park. In the sentence "You met at the park to run", "to run" is the infinitive phrase.
Opening you eyes is an infinitive phrase. This is taught in English.