Question

who has informed u so? change into passive voice​

Answer 1

Question -

Who has informed you so?

Answer -

By whom have you been informed so?

Explanation -

First notice the tense of the given sentence.

The presence of has informed shows that it is in present perfect tense.

When the voice is changed to passive voice, the verb, been, is added and has changes to have .

Summarizing,

Active voice - has + past participle of verb

Passive voice - have + been + past participle pf verb.

Now, who changes to by whom for passive voice. Since the object now becomes the subject.

Hope This Helps You!

Answer 2

Answer:

By whom have you been informed so?

Explanation: