Which of the following parts of speech do all sentences contain? a. an adverb b. an adjective c. a verb d. a preposition

i would say that these are the two thesis statements best for a literary analysis essay on recurring themes in shakespeare's romeo and juliet:

1.  in romeo and juliet, shakespeare demonstrates that love comes in a variety of forms, be it romantic, familial, or between friends.

2.  shakespeare explores the struggle for identity through the character of juliet in his play romeo and juliet.

the other theses aren't reoccurring in this play. 

explanation:

the tone of the passage is sympathetic to the forbidden love of romeo and juliet. the nurse plays a significant role in the play. she is responsible for making their meeting again possible. additionally, there is a sense of warning in the choice of words of the nurse. she seems to be authoritative when she calls romeo "scurvy knave", and at the same time the fact that she addresses to him as "sir" reflects respect. the nurse is "vexed", this word describes her confused state of mind. on the one hand, she finds romeo a fine and eloquent man, but on the other, it is thought that man's nature forces men to try to trick women.