Question

Michael was watching TV_____ his father came in.
A. when        B. while      C. as soon as

Answer 1

A

试题分析：A. when 当…时候 B. while当…时候      C. as soon as一…就；句意：迈克尔正在看电视时，他的爸爸进来了。came这个动词是个瞬间动词，只能与when连用，故需A
点评：when 既可以与延续性动词连用，也可以与瞬间动词连用，而while只能与延续性的动词连用，强调两者同时进行，多用进行时态的形式。