He got the answer to the riddle as quick as a flash.

他一下子就猜中了谜底.

辞典例句

In the stock - exchange deals he had been as quick as a flash at times.

他有时候像闪电般地交割证券交易所的买卖.

互联网

As quick as a flash, he chopped off the turtle's head.

一瞬间, 他就把乌龟的头砍了下来.

互联网