Can you please tell me what "first" is in the following sentence.

It was up to another American, Robert Fulton, to develop the first widely successful steamboat.

I think "first" is an adjective modifying steamboat. Thanks, Kris

You are correct

thank you so much!

Just a rule of thumb: Adverbs answer the questions -- when, where, how, how much, how many, why, or negative/positive.

Actually, in the sentence you provided, "first" is not an adjective modifying "steamboat." It is actually a noun functioning as the object of the verb "develop."

To identify the role and function of "first" in the sentence, we can analyze the sentence structure:

"It was up to another American, Robert Fulton, to develop the first widely successful steamboat."

In this sentence, "first" refers to the earliest or initial steamboat that was widely successful. It is used as a noun to indicate the specific one being referred to.

To determine the part of speech of "first," we can ask ourselves, "What did Robert Fulton develop?" The answer is "the first widely successful steamboat." Here, "first" is a noun, as it is the object of the verb "develop."

So, "first" is not an adjective modifying "steamboat" in this sentence. It is a noun serving as the object of the verb "develop" and indicating the specific steamboat being referred to as the earliest successful one.