用括号中所给单词的正确形式填空。
His pencil is in the pencil box.This is _________ (I).
_________ (it)are nice baseballs.
I _________ (be)an English schoolgirl.
This watch is not _________ (your).
These are _________ (Lily)photos.
Look at the picture! This is my sister and _________ (that)are my brothers.
That _________ (be not)my ruler.
I have some _________ (watch).
This is _________ (we)room.
Is _________ (his)your father?