—Youlooksoworried.What’sthematter?—Idon’tknowhowto

—You look so worried. What’s the matter?

—I don’t know how to ______ these boring problems.

A．deal with B．dealt with C．look up D．look for

【解析】句意：-你看起来如此担心，怎么了？-我不知道怎样处理这些令人厌烦的问题。deal with处理；dealt with是过去式形式；look up查阅；look for寻找。根据句意可知，这里是处理问题，应该用短语deal with，How是疑问词，后面跟动词不定式，故应选A。