VOA一分鐘英語：Unless 和 as long as 區(qū)別是什么？

單詞 “unless” 和搭配 “as long as” 都可以用來表示一件事情發(fā)生的條件。雖然這兩個(gè)說法非常相近，但它們的用法是有區(qū)別的。
 
Hi, I’m Georgina from BBC Learning English. In today’s lesson we look at the difference between unless and as long as.
Unless and as long as can be used to replace ‘if’ in different situations.
Let’s have a look at some example sentences.
I will go to the party if you come too.
I will go to the party as long as you come too.
Both of these sentences have the same meaning. Notice that the verb after ‘if’ and as long as is positive.
Now look at these sentences.
If you don’t do your homework, you can’t watch the film.
Unless you do your homework, you can’t watch the film.
Both of these sentences have the same meaning, but notice that the verb after ‘if’ is negative and the verb after unless is positive.
Bye!
 
用法總結(jié)
1 “Unless（除非）” 和 “as long as（只要）” 都可以用來引出一件事發(fā)生的條件，在不同的情況下，可代替 “if” 使用，而句意保持不變。
I will go to the party if you come too. = I will go to the party as long as you come too.
If you don’t do your homework, you can’t watch the film. = Unless you do your homework, you can’t watch the film.
 
2 搭配 “as long as” 的意思相當(dāng)于 “if”，可以用來表達(dá) “只要某條件符合，那么就...”。
I will go as long as you go. 
As long as we don’t make any loud noises, the baby will sleep fine.
 
3 單詞 “unless” 的意思相當(dāng)于 “if not”，可以用來表達(dá) “除非某條件符合，否則就...”。
Unless I go home now, he’ll be worried.
We won’t be there on time unless this traffic clears quickly.