when:表示一件事在某一时间发生,例I came home when 7o'clock.(我七点回家。);while:表示一件事发生时另一件事也在发生,I came home while she was watching TV.(我回家时她正在看电视。);among:在三者(或三者以上)中,区别于between(两者中);as soon as:一......就......Please call me as soon as you arrive at home.(请一到家就给我打电话。)。
考驾照网【kaojiazhao.COM】