didn't like the job much at first.
起初我并不很喜欢这个工作。
The situation was more complicated than they had at first realized.
形势比他们最初意识到的更为复杂。
At first the place was strange to me.
起先我对这个地方不熟悉。
We left at first light.
我们黎明时离去。
If at first you don't succeed, try, try again.
一次不成功就反复尝试。