Question

India and Maharashtra can progress only when there is oneness of interest.
(rewrite using 'unless')

Answer 1

India and Maharashtra can't progress unless there is oneness of interest

Answer 2

India and Maharashtra can progress Unless there is oneness of interest.

The word ‘unless’ means the same as if or not.

Normally the word unless is followed by the present tense, a past tense, or a past perfect tense. order of the clauses doesn't matter with sentences using unless.

Unless is used instead of if...not in conditional sentences of all types.