What is the verb phrase for following sentence what an incredible sight that surely is?

The verb phrase in the sentence "What an incredible sight that surely is" is "surely is".

Here's why:

* "is" is the main verb, indicating a state of being.

* "surely" acts as an adverb modifying the verb "is", emphasizing the certainty of the statement.

Together, "surely is" forms the verb phrase that describes the state of the sight being incredible.