涉及省略结构if not, not的语法题
请看下面的题，考查什么样的省略结构：
If the weather is fine, we’ll go. If _________, _________.
A. not, not B. no, no C. not, no D. no, not
【分析】此题应选A。If not, not. 为 If the weather is NOT fine, we will NOT go. 全句意为“如果天气好, 我们就去；如果天气不好，我们就不去”。该句的特点是：后句与前句的用词和句式完全相同, 只是前句为肯定，后句为否定，为了简洁起见, 于是将后句与前句相同部分省略，只保留否定词 not。又如：
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。
请再看以下例子(只保留否定词not)。如：
“Can you repair it yourself?” “I am afraid not.” “你自己会修吗?”“恐怕不行。”(=I am afraid I can't repair it myself.)
“Did you know anything about it?” “Not until you told me.” “这事你以前知道吗?”“你告诉我才知道。”(=I didn't know anything about it until you told me.)
“Will it rain today?” “I hope not.” “今天会下雨吗?”“希望不会。”(=I hope it will not rain today.)