(
课件网) 1. 构成：to + 动词原形（有时不带to） e.g. To save time is to lengthen life. You can take a horse to the water but you cannot make him drink. This charity aims to help people (to) help themselves. 2. 不定式的否定式：not (to) do，never (to) do e.g. He was anxious not to be misunderstood. She wished never to see him again. 不定式的一般形式、进行体和完成体形式 1 不定式的否定式否定的是动词不定式，与谓语动词的否定式意义不同。 提示 3. 六种语法形式 不定式没有“时”的标记，也不受“人称”和“数”的制约，但有“体”和“态”的区分。 提示 不定式 主动态 被动态 一般形式 (to) do (to) be done 进行体形式 (to) be doing / 完成体形式 (to) have done (to) have been done 完成进行体形式 (to) have been doing / 4. 各种语法形式的意义 （1）一般形式：通常表示动作发生在谓语动词的动作之后，也可能同时发生。 e.g. Let’s go out to get some fresh air. （to get在go out之后发生） I’m glad to hear you’re feeling better. （to hear与am glad同时发生） （2）进行体形式：通常表示在我们谈论的时间（现在或过去）正在进行的动作。 e.g. A new order seems to be emerging. He happened to be looking through the medical book “Gray’s Anatomy” at the time. （3）完成体形式：通常表示动作发生在谓语动词表示的动作之前。 e.g. I’m sorry to have kept you waiting. （to have kept在am sorry之前发生） He is said to have left Shanghai. （to have left在is said之前发生） （4）完成进行体形式：表示动作发生在谓语动词的动作之前，并强调动作的连续性。 e.g. She is said to have been writing the novel for years. The president was reported to have been flying across the Atlantic. 不定式的完成体还常用于谈论“想象中”的过去未曾发生的动作，如“She was to have left earlier, but it rained.”。 提示 （5）被动态：表示不定式的逻辑主语是不定式动作的承受者。 e.g. They were all waiting for the gate to be opened. He is sure to have been taught by a good musician. 注意如下场合： （1）在情态成语之后 常见情态成语：would rather / would sooner / would (just) as soon (宁愿)，may / might (just) as well (不妨，可以)，cannot but / cannot help but (不能不，不得不)等 e.g. I’d rather meet him here on my own home ground. If no one else wants it, we might as well give it to him. I cannot but agree to your decision. They would rather work than live on welfare. 不带to不定式的使用场合 2 would rather后接that分句时，分句谓语动词用虚拟语气，如“I would rather that you went now.”。 提示 （2）rather than / sooner than置于句首时 e.g. Rather than cause trouble, he left. Sooner than marry that man, she would earn her living as a waitress. （3）“使役动词+宾语”、“感觉动词+宾语”、“have known +宾语”之后 e.g. The very thought of drink made him feel sick. He won’t have us criticize his work. We feel the house shake. I have never known that man smile. 当 rather than / sooner than 出现在句中其他位置时，其后不定式既可带to也可不带to。 提示 注意：被动语态都要用带to不定式。 e.g. We were made to attend meetings every day. He was seen to enter the building about the time the crime was committed. He ha ... ...
