I wasn`t born yesterday.

It`s my treat this time.

The sooner,the better.

When is the most convenient time for you?
(when you want to invite sb to have a dinner or ask for a help,you should ask them when is the most conevenient time for him)

Take your time.


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我又不是三岁小孩。

这次我请客。

越快越好。

你什么时候有空?

别急，慢慢来。