,I found the job boring,but soon I got used to it.
A.To start with B.First of all
C.Without doubt D.After all
A
【详解】
句意:起初,我觉得工作很无聊,但是很快我就适应了。
考查副词短语。A. To start with起初;B. First of all首先;C. Without doubt毫无疑问;D. After all毕竟。根据but soon I got used to it.但是很快我就适应了,可推知是起初觉得工作很无聊,所以A选项符合题意;故答案选A。