in case 与 if 都能引出条件从句,请问它们有什么区别?
in case(如果,万一)引出条件从句时,一般是指将来时间(尽管动词时态是一般现在时)或过去将来时间,而 if 引出的条件从句可以指任何时间(现在、过去、将来)。
-
In case I forget, please remind me about it. (ALD) 如果我忘了，请提醒我一下。
-
In case the house burns down, we'll get the insurance money. (LDCE) 如果房子被烧毁,我们将领到保险金。
-
. . . police patrolled the streets in case anyone tried to leave the shelters too soon. (NCE 3, L.7) 警察在街上巡逻，以防有人试图过早地离开防空洞。
-
Leave her car where it is and put plainclothes on watch in case they try to come back to it. (Dan Brown, The Da Vinci Code) 把她的车留在原地，并派便衣监视，以防他们回头用车。(《达·芬奇密码》)
下面两个句子最能说明 in case 与 if 的区别：
(a) I'm taking an umbrella in case it rains later on. 我拿着一把伞，以防一会儿下雨。
(b) I'll take an umbrella if it rains later on. (AEP) 要是一会儿下雨,我就拿一把伞。
在句(a)中“我现在拿着一把伞”已成为事实，而不管天晴，还是下雨。而在句(b)中“我是否拿伞”决定于“过一会儿是否下雨”。