Question

同义句 Do you know whose computer this is

Answer 1

1.Do you know whose computer this is?

=Do you know (whose) the computer (is)?

2.没错,就是用used up:

He looked so tired as if he had (used up) all his strength.

use...up是及物动词短语,必须要加宾语,意思是“用完/耗尽...”；

此as if引导的方式状语从句使用了虚拟语气,所以从句用了过去完成时,即谓语结构为“had + 动词过去分词”.