between ourselves (或 you and me)

in confidence

咱们（或你我）私下说说

just between you and me, I don't think it was going to happen.

只是咱们私下说说，我认为这事不会发生的。

(in) between times (或 whiles)

in the intervals between other actions

在间歇期间

between you and me

In the strictest confidence.

你知我知，天知地知：表示非常信任

in between

In an intermediate situation

在中间的状况

My roommates disagreed and I was caught in between.

我的室友不同意，我被夹在中间进退两难

in between times

During an intervening period; in the meantime

穿插着；同时：在其间的一段时期；同时

has written several books and teaches in between times.

在写书的同时也教书