1、at one's last gasp垂死挣扎,最后的拼搏

The enemy are at their last gasp.敌人在做垂死的挣扎。

2、have the last word最终决定,最后裁决

In our company the manager has the last word.在我们公司经理有最后决定权。

3、in the 〔one's〕 last resort最后的手段,最后的凭借

In the last resort we can always swim back.大不了我们可以游回来。