lack

我们这所房子缺的是储物空间。

What we ___lack in this house is space to store things.

我们仍缺少一些破案的关键证据。

We still ___lack some crucial evidence to solve the case.

由于缺乏睡眠，他今天感到非常疲惫。

He felt extremely tired today because of a ___lack of sleep.