Question

I can do the sum. (voice change)
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Answer 1

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The sum can be done by me.

Explanation :

To change sentences having present/future modal into passive voice, auxiliary verb "be" should be placed between the modal and the past participle form of the verb.

Structure :

Object + modal + be + past participle form of the verb + by + Subject

Answer 2

ANSWER ⤵️

The sum can be done by me.