Question

Which form of careful best completes this sentence?

Tomorrow at training, Frances must be __________ than she was today.

A.
carefully

B.
more careful

C.
most careful

Answer 1

more careful (B) than today (because it compares with today and tomorrow .)

hope it helps :)

Answer 2

So,

Normally, this type of sentence means that (subject) already was careful, and that she has to be more careful.

She can't be most careful, because that is impossible.

Therefore, option B is the correct answer.

Frances must be more careful than she was today.