Unit 1 Food matters Grammar & Usage To-infinitives as subjects and predicatives 课件-2021-2022学年高一英语牛津译林版（2020）选择性必修第一册

Unit 1 Food matters Grammar & Usage To-infinitives as subjects and predicatives Functions of to-infinitives Object 宾语 Subject 主语 Predicative 表语 Attributive 定语 Adverbial of result 结果状语 Adverbial of purpose 目的状语 Adverbial of reason 原因状语 Subject/ Object complement 主补/宾补 To-infinitives: to+ the base form of a verb 时态 语态 一般时 进行时 完成时 被动语态 主动语态 to have done to be doing to be done to do （做主语时谓语动词一般用单数形式） To say is one thing and to do is another. 说起来容易做起来难。 动词不定式作主语 动词不定式作句子的主语时可以用形式主语 it 代替，将不定式置于句末， 平衡句子结构。 乱扔垃圾可耻 众口难调 it 作为形式主语时，常见句型有： It + is +adj. + ( for sb) to do sth ( adj 修饰物） It + is +adj. + ( of sb) to do sth ( adj 修饰人） It + is + n. + to do sth It takes sb some time/money/effort to do sth It is a shame to litter. It is hard to please all. 4 注：单个不定式作主语时，谓语动词用单数形式；两个及以上不定式作主语时，谓语动词用复数形式；但作为一个整体时，谓语动词用单数形式。 到哪里去度假以及何时去度假还没有决定。 Where to go on a holiday and when to go f