Out of gas:

1). Without gasoline (in a car, truck, etc)

2). Tired; exhausted; worn out

这个短语的字面意思是车没有汽油了，但是它的引申义是形容人累得精疲力尽的状态。

造句：

1). This car will be completely out of gas in a few more miles.

2). I have been playing tennis matches for more than three hours, and I’m really out of gas.