The police didn't find
any
evidence.
Change to past simple passive

the correct answer is:

from context clues heliotrope is probably a flower.

a heliotrope are peruvian plants that have small purplish plants.

the characters in string all have major secrets that they strive to avoid revealing throughout the play.

hm, switch the relative; nominative and indefinite; objective ? not too bright in the knowledge of the english.

from the political point of view it could be said that the candidate   is an effective speaker because she takes a strong position on the issue. it is an open discussion but probably she is making a presentation and can choose which subjects she wants to address. she is very likely to attain her aim which is to convince voters to accept her proposal.