verb
1
BAD : I couldn't talk English in those days.
GOOD : I couldn't speak English in those days.
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speak English/French/Thai etc (NOT talk ): 'Do you speak Italian?' 'I didn't know you could speak Greek.'
2
BAD : I'd like to talk you about a dream I had last night.
GOOD : I'd like to tell you about a dream I had last night.
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When there is something that you want someone to know, you tell them about it: 'She told me about her holiday plans.'
When you have a conversation, you talk (to someone) about something: 'We talked about where we could go at the weekend.'
3
BAD : There's something I'd like to talk you about.
GOOD : There's something I'd like to talk to you about.
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talk to sb ( about sth ): 'The manager would like to talk to you when you have a moment.'
4
BAD : I didn't want to talk with him because I was in a hurry.
GOOD : I didn't want to talk to him because I was in a hurry.
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In British English the usual phrase is talk to someone: 'Who were you talking to just now?'
Note that in American English both talk to and talk with are used.