Question

He was obliged to go (voice change )

Answer 1

HEY MATE
HERE IS YOUR ANSWER


He was obliged to go ( by him )
ANS. He obliged him to go

HOPE IT HELPS

Answer 2

Here, the doer or the subject is not mentioned. So we need to add a subject that is generally used in these cases.

Given sentence is in past tense passive form.

It's rule is

Obj + Was/were + verb 3rd + subject.

Here, infinite (to go) and obliged are used. He is object for the passive form. Subject is ommited. Generally, circumstance is used as a subject in these cases.

Hence the active voice of given sentence is

Circumstances obliged him to go.

Hope you understand