7.7 The Infinitive

• Are Infinitives Really Verbs
• A Common Form Be -Adjective-Infinitive
• Infinitives in Everyday Speech

时态和语态

时态	主动态	被动态
一般式	to do / do	to be done / be done
进行式	to be doing / be doing
完成式	to have done / have done	to have been done / have been done
完成进行式	to have been doing / have been doing