If not, not是一句省略句,如:
If it is cheap, I’ll buy it. If not, not. 如果这东西便宜,我就买;如果不便宜,我就不买。
If you study hard, you’ll succeed. If not, not. 你若努力,你就会成功;你若不努力,你就不会成功。
If you start at once, you’ll catch the train. If not, not. 你若马上动身,你就会赶上火车;你若不马上动身,你就赶不上火车了。
If it is interesting, I’ll read it. If not, not. 如果有趣,我就读;如果没有趣,我就不读了。
请问:这类句子只能用一般现在时吗?它也可以用其他时态吗?
凭感觉,这类从句通常确实是用一般现在时,正如你所举的例子一样。即:
1. If it is cheap, I’ll buy it. If not, not.
= If it is cheap, I’ll buy it. If it is not cheap, I won’t buy it.
2. If you study hard, you’ll succeed. If not, not.
= If you study hard, you’ll succeed. If you don’t study hard, you will not succeed.
3. If you start at once, you’ll catch the train. If not, not.
= If you start at once, you’ll catch the train. If you don’t start at once, you won’t catch the train.
4. If it is interesting, I’ll read it. If not, not.
= If it is interesting, I’ll read it. If it is not interesting, I will not read it.
但是不是意味着除了一般现在时外,这类if从句就不能是其他时态了呢?按理说不会这样,所以查了一些词典,在《麦克米伦高阶英语词典》的if词条,查到了下例句:
Has anyone dealt with the technical problems? And if not, why not? 有人来解决这些技术问题了吗?如果没有,那是为什么?
这个句子与你的句子稍有不同,但应该也能说明一定的问题。此句中的if not=If no one has dealt with the technical problems。即从句用的是现在完成时。
还希望其他各位老师加以补充!