The two noun phrases in Douglass's sentence are "many daring exploits" and "to their credit," and the head noun in each phrase is "exploits" and "credit."
A noun phrase is a group of words which presents a noun and determiners or modifiers. It functions as a noun would function in the structure of the sentence. The head noun is the main word in the group.
In the sentence we are analyzing here, we can identify the noun phrases and the head nouns as follows:
Learn more about noun phrases here:
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