低效的'用英语(adj)怎么说?

inefficient

even if 即使 要与上下文的时态与含义配合 例：

Even if he is poor, he looks happy.
即令他穷，他看上去很快乐。

Even if she comes it will be too late.
就让她来，也晚了。

Even if she were very busy, she would go.
既使她很忙，她也会去的。