完形填空:通读短文，掌握大意，选出一个最佳答案。共10题，每小题1分，满分10分。
I am________American. My name________ Lily. I am a new student. I am twelve. Now I am_________ Class Six, Grade One, No.5 Middle School. My teacher is Miss Li. I have a sister. ________   name is Lucy. We _________ twins（双胞胎）. We look________. But she is in a different school.
I am on duty(值日)today. I can′t look after(照顾)my sister._________school I help my teacher put her book, map and pictures on her ________. I tell her everyone is here, ________  I am wrong. Jim is not at school. I don′t ________ where he is. I think he is at home.

A．a B．an C．the D．/

A．am B．is C．are D．be

A．in B．on C．to D．at

A．She B．Hers C．She′s D．Her

A．is B．are C．am D．be

A．same B．different C．the same D．the different

A．On B．At C．To D．From

A．chair B．book C．desk D．table

A．and B．or C．but D．so

A．think B．thank C．know D．do