1. A predicative nominative is a noun or a pronoun which follows a linking verb and refers to something before that verb. In your case, the correct answer is B, because "a shelter" goes after the linking verb "is", and refers to "a lean-to".
2. A participle has the form of infinitive + ing. In this case, the answer is D, flourishing.
Answer: 1. Dizzy, 2. dees and 3. quickly.
Explanation: The connotation of a word is the meaning that is given by the context of by the readers based on their emotions or personal experiences. It is the antonym of denotation which is the literal meaning of a word, in this activity, we must select the correct synonym or denotation of each underlined word. The first word "giddy" is a synonym of "dizzy." The second word "doth" is the archaic third person singular of the verb "do" so it is does" and the last word "amain" is a synonym of "quickly."
To be honest i dont think it changes anything.