be动词后的宾语to do和doing都行吗为什么有时用to do有时用doing但是我见过的大多数都是doing 有什么区别吗?还有一个问题 If you tell a friend you are going to their house for dinner为什么用theirZ不用his or her?【课本原句】还有这个句子If someone invites you to meet them at 4:00也是一样的情况，也是课本原句。
问题描述：
be动词后的宾语to do和doing都行吗
为什么有时用to do有时用doing但是我见过的大多数都是doing 有什么区别吗?
还有一个问题 If you tell a friend you are going to their house for dinner为什么用theirZ不用his or her?【课本原句】
还有这个句子If someone invites you to meet them at 4:00也是一样的情况，也是课本原句。
答
1.be 动词后面的成分叫 “标语”,不叫宾语.doing和to do都可以跟be后面,做表语.My job is cleaning the window./My job is to clean the window.都对2.这句话用his or her是可以的,用their也行,前面的a friend 是泛...