be动词的用法（a）I am Millie. (b)He is Andy./She is Millie./I

be动词的用法
（a）I am Millie.
(b)He is Andy./She is Millie./It is Lily's dog Spotty.
(c)We/You are classmates./They are my new friends.
(d)Andy is my cousin./Millie and Jill are good friends.
在(a)、(b)、(c)三组例句中,主语都是______,谓语都是______.
在(d)组例句中,主语是______.