把a当作b用英文怎么说

把a当作b用英语可以说是 "treat/regard/consider a as b"。

来源：这个表达方式在英语的日常使用中十分常见，表示的是把一个东西当做另一个东西来看待、对待或考虑。

例句：

She treats her job as her top priority. 她把工作当做重中之重。
They regard the meeting as an opportunity. 他们把会议当作一个机会。
I consider him as a friend. 我把他当作朋友。