pretend|pretended|pretending

你只是假装感兴趣吗？

Were you just ___pretending to be interested?

她并不是真的受伤，她只是在假装。

She's not really hurt - she's only ___pretending.

他假装不在意，但我知道他其实在意。

He ___pretended he didn't mind, but I knew that he did.