(8) 引导时间状语从句,与while意义相近 We get wiser as we get older. 随着我们长大,我们也变得越来越聪明。 (9) 引导原因状语从句,与 because的用法相近 As it was getting very late, we soon turned back. 因为越来越迟了,所以我们不久就回来了。