Question

1. He lent me a book, which interested me very much.

2. He lent me a book, and it interested me very much.

3. He lent me a book, interesting me very much
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Can #2 be changed into #3? Are they all grammatical and the same in meaning?

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4. I trust him, who is very honest.
5. I trust him, for he is very honest.
6. I trust him, being very honest.
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What about these ones? Are they all grammatical and the same in meaing? Is #6 correct?

Answer 1

The -ing phrasing is not the best. It's not incorrect; it's just not used very much.

1, 2, and 5 are the best sentences here.

Answer 2

No. 1 no comma required
No. 2 correct
No. 3 wrong