grammar question: should I use "his" or "him&

[hereinchina]

Hello,
I'm not sure if I should use the word "them" or "their" in sentences number one and two. Or are both words grammatically correct? In sentence number 3, should I use "his" or "him"
1. If you can read people's minds, you can know what they are thinking without "them / their" telling you.
2. To read somebody's mind means to know what someone is thinking, or what they are feeling, without "them / their" telling you."
3. I can read my father's mind, I can know what he is thinking without "him / his" telling me.

[fluffyhamster]

It would probably be better (or at least save me having to summarize things somewhat unnecessarily!) if you read up on this yourself, and a good place to start is Merriam-Webster's Dictionary of English Usage, available completely for free and in FULL preview on Google Books; the relevant entry is 'possessive with gerund' (on pages 753-755 - do a search for 'gerund'). But actual ELT/EFL references may have more concise and/or relevant information, so I'll try to check in a few staples and get back to you if I find anything especially interesting.

[fluffyhamster]

Common references such as Swan's PEU, Leech's A-Z, and the COBUILD Grammar basically label the possessive form as formal and the object pronoun form as informal. The Grammar Book however goes a bit further and observes in a section headed 'Gerund complements versus subject-participle complements' that "For some speakers of English there is a semantic contrast for verbs taking both the possessive gerund complement and the subject-participle construction: a) I appreciate his taking care of the dog (versus) b) I appreciate him taking care of the dog. Such speakers report a greater focus on the entire event in the possessive-gerund complement (that is, in a) and a greater focus on the agent NP in the subject-participle construction (=b)."

[hereinchina]

Hello,
Thanks for the links and taking time to answer my question.
Best wishes