He went home for lunch the clock struck twelve.
A. while
B. immediately
Cright away
D. at once
网友回答
A. while
(答案→)B. immediately
C. right away
D. at once
解析：本题中的immediately已经转换成连词“一…就…”，相当于as soon as…；句义：钟一敲12点，他就回家吃饭了。While当…时；然而；尽管；CD两项都是短语，不能在句中做连词引导从句。故B正确。