Thank you for your help. One more question about the verb send goes as follows.

1. He sent me a book. [active]
2. I was sent a book by him.[passive]
3. A book was sent (to) me by him.[passive]
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#3 is grammatical. It has no problem.
What about #2? Is it grammatical? In a grammar book here, it is correct. In another grammar book here, it is incorrect. Which one is right?

1 answer

2 is correct as it's written.

3 is correct as long as you use "to" -- that word is not optional in that sentence.