阅读理解。

     Today is Friday. The students on duty come to school early. They clean the classroom and the

blackboard . Then they put the desks and chairs in good order (顺序) . One of them takes down

(取下) an old map and puts up a new map of world on the wall . After all this, all the students come.

They sit in a nice classroom.  Mr Zhou is very glad to see the clean classroom. He thanks them for it.

1.Today ______ clean the classroom .

A .all the students

B. some students

C. one student

D. the teacher

2. When class begins, the classroom is ______.

A. in good order

B. on duty

C. big

D. not clean

3.How does Mr Zhou feel when he sees the clean classroom ?

A. sad

B. angry

C. glad

D. sorry

前牙反骨骼Ⅰ型其诊断标准是（）。

A.ANB角＜0°

B.ANB角＜2°

C.ANB角＞5°

D.ANB角＜－5°

E.ANB角≥0°