精选优质文档-倾情为你奉上八年级英语动词不定式用法梳理动词不定式是由“不定式符号to+动词原形”构成的一种非谓语动词结构。有些动词不定式不带to,动词不定式可以作句子的主语、表语、宾语、定语、补语、状语或单独使用。不定式保留动词的某些特性,可以有自己的宾语、状语等。动词不定式和它后面的宾语、状语等一起构成短语,叫作不定式短语。一、用作主语直接把动词不定式置于句首的情况不多,多数情况用it作形式主语,把真正的主语动词不定式置于句末,特别是不定式短语较长时。动词不定式作主语,谓语动词用第三人称单数形式。带疑问词的不定式短语作主语常置于句首,复合不定式结构作主语常置于句末。如:1. I t is our duty to try our best to deal with these problems.2.The head teacher said it was necessary to talk with his mother. 3.How to learn English well is important. 4.To see is to be