Question

I have bought some books convert into passive form​

Answer 1

Some books have been bought by me.

• When the active sentence contains "has","had","have"; then the passive sentence will contain "has been", "had been" and "have been".

• And,rest of the sentence will be changed as per the normal voice changing guidelines. (Subject and Object location replacement and other grammatical necessities.)

• In this way,we changed the given sentence into it's passive voice form.

Answer 2

Here is the correct answer along with explanation:

Some books have been bought by me.

Explanation

When we change voice of a sentence, we have to change the active voice verb into passive voice verb or vice versa.  

It is a present perfect tense.  

The active and passive voice tense forms in this tense are as follows:

Present perfect active = S+has/have + V3  +O

Present perfect passive = O+has/have + been + V3  +by+S