Question

They do not do sums into passive voice

Answer 1

Answer:

Sums were not done by them.

Answer 2

Answer:

Active-

They do not do sums.(Simple Negative Present Tense)(sub+do not+V1+obj)

Passive-

Sums are not done by them.

Formula-(Obj+is/aren't+V3+Obj.)(Simple Negative Present Tense)

Hope It Helps