一、incase引导的状语从句根据语境的不同,incase既可表示“如果”“万一”,引导条件状语从句;也可表示“以防(万一)”,引导目的状语从句
下面两道真题均选incase:1
Leaveyourkeywithaneighbor______youlockyourselfoutoneday
(北京卷)A
eversinceB
evenifC
soonafterD
incase2
Myparentsliveinasmallvillage
Theyalwayskeepcandlesinthehouse______thereisapowercut
(重庆卷)A
unlessC
incaseD
sothat【解析】两道题都选incase,均表示“以防万一”
二、before引导的状语从句尤其要注意“it+be+一段时间+before…”这一句型
ThefieldresearchwilltakeJoanandPaulaboutfivemonths;itwillbealongtime______wemeetthemagain
(安徽卷)A
afterB
beforeC
sinceD
Hewastoldthatitwouldbeatleastthreemoremonths______hecouldrecoverandreturntowork
(江西卷)A
beforeC
sinceD
that【解析】两道题均before
第1题涉及的句式为:Itwillbealongtimebefore…,意思是“要过很久才会……”;第2题涉及的句式为:itwassometimebefore…,意思是“在……之前过了一段时间”,通常可转译为“要过一段时间才会……”
三、while引导的状语从句尤其要注意while表示“尽管”“虽然”时的用法(此时它引导的不是时间状