1. He calls his wife "sweetheart."

Question

2. He calls his wife "Sweetheart."

3. He calls his wife Sweetheart.
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Are they all grammatical? Which ones are correct?

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4. She begged one more chance of her.

5. She begged her one more chance.

(Is #4 the same as #5? Are both grammatical?)

Answer 1

#1 is correct; 2 an 3 aren't.

I'd use #4, but #5 is not correct unless you insert "for" after "her."