我不会去参加聚会的, 除非他也去.(如果他不去,我也不去.)
4.You will be late unless you leave immediately.
如果你不马上走,你将会迟到的.(=If you don't leave immediately, you will be late.)
难点作文地带提示：用条件状语从句时要注意时态的正确使用,当主句是将来时的时候,从句要用一般现在时.
lHe will not leave if it isn't fine tomorrow.
一般将来时， 一般现在时
lThey are going to have a picnic if it doesn't rain next week.
一般将来时, 一般现在时
[编辑本段]四、原因状语从句
要点: 由连词because, since, as引导, 也可由for, now that 等词引导
1.I didn't go to school yesterday because I was ill.
我昨天没去上学，因为我生病了。
2. Since everybody is here, let's begin our meeting.
既然大家都来了, 让我们开始开会吧.
3. As you are in poor health, you should not stay up late.
既然你身体不好, 你就不该熬夜.
4.I asked her to stay to tea, for I had something to tell her.
我请她留下来喝茶,因为我有事要告诉她.
.难点::because , since , as , for,辨析
1） because语势最强，用来说明人所不知的原因，回答why提出的问题。当原因是显而易见的或已为人们所知，就用as或 since。
I didn't go, because I was afraid.
Since /As the weather is so bad, we have to delay our journey.
2） 由because引导的从句如果放在句末，且前面有逗 号，则可以用for来代替。但如果不是说明直接原因，而是多种情况加以推断，就只能用for。
He is absent today, becaus e / for he is ill.
He must be ill, for he is absent today.
[编辑本段]五、目的状语从句
要点： 目的状语从句由连词that, so that, so…that , in order that 引导。
1.so that 以至, 以便
I'll run slowly so that you can catch up with me. (目的)
我将慢慢跑以至你能赶上我。
I opened the window so that fresh air might come in. (目的)
我把窗户打开以使新鲜空气可以进来。
2.in order that=so that:为了
We shall let you know the details soon in order that you can/may make your arrangements.
不久我们将会让你知道详情,以便你们能够做出安排。(目的)
[编辑本段]六、结果状语从句
要点：结果状语从句由连词( so )that, so…that, such…that, so much/many…that引导。
1.so…that 如此…以至于
The scientist's report was so instructive that we were all very excited.
科学家的报告很有启发性，我们感到很兴奋。
He always studied so hard that he made great progress.
他总是那么努力，结果他取得了很大的进步。
2. such…that 如此。。。以至
It's such nice weather that all of us want to go to the park.
天气是如此的好，我们大家都想去公园玩。
3.比较：so和 such
其规律由so与such的不同词性决定。such 是形容词，修饰名词或名词词组，so 是副词，只能修饰形容词或副词。 so 还可与表示数量的形容词many, few, much, little(这四个形容词表多或表少时)连用，形成固定搭配。liuxuepaper.com