talk big or big talk
吹嘘/吹牛
He started talking big after winning the match!
他赢了一场之后，就开始吹牛了。

small talk
闲聊
weather -- sports -- news
天气，运动，新闻，都可以很好地开启 small talk

sweet talk
甜言蜜语
He sweet talked her into becoming his girlfriend!
他对她说一些甜言蜜语，想让她成为他的女朋友！

pep talk
激励人心的话
I need some pep talk after going through this rough time.
经历过这段难熬的时间，我需要一些鼓励！

与talk相关的俚语
all talk and no action
总说却不做
You are saying that you can be something in the future, but you are all talk and no action!
你总说你将来会做点什么，可是你总是说却不付出行动。

be talking through your hat
胡说，瞎说！
Don't pay Jack any mind. He is talking through his hat again！
别理Jack, 他又开始瞎说了！