Question

as as possible和as as one can一样吗

Answer 1

1. 基本一样.
如：I'll study as hard as possible.
=I'll study as hard as I can.
2. 但是,如果句子时态是过去时的时候,
则as ..as possible=as ..as one could≠as ..as one can
原因很简单,can也是有时态变化的,其过去式为could.
如：The thief ran as fast as possible when he saw the policeman.
=The thief ran as fast as he could when he saw the policeman.

Answer 2

意思一样，相当于同义短语