新概念英语语法解析现在进行时

saya

现在进行时

　　表示现在正在进行的动作。

　　构成： 主语＋be动词＋动词的现在分词＋其它成分（现在分词的构成见附录）

　　We are having lunch.

　　He is reading a book.

　　The dog is running after a cat.

　　The boys are swimming across the river.

　　★变疑问句将be动词移到句首

　　Are we having lunch?

　　Is he reading a book?

　　Is the dog running after a cat?

　　Are the boys swimming across the river?

　　★变否定句在be动词后面加 not

　　We are not having lunch.

　　He is not reading a book.

　　The dog is not running after a cat.

　　The boys are swimming across the river.

　　★特殊疑问句：what, which, how, where, who, etc.

　　疑问词＋动词＋主语＋现在分词

　　What are you doing?

　　What is she doing?

　　What is the dog doing?