在机体抗感染中起主要作用的是
A.IgA B.IgG C.IgE D.IgM E.IgD
参考答案:B
This is my school. There are many trees and flowers. The teaching building is big and tall. There is a big playground in our school. It’s very nice to have it. After 4:30 in the afternoon, many students come to the playground to play football and some students play table tennis in the table tennis room.
There are 1,200 students in 30 classes in our school. The students all like to study. The teachers in our school are very good. They help the students to study and sometimes play with them. All the students like them.
小题1:The teaching building is _____.
A.small
B.old
C.big and tall
D.big小题2:It’s very nice for this school to have ____.
A.trees and flowers
B.a playground
C.students
D.teachers小题3:There are at least (至少) _____ students in one class.
A.45
B.40
C.75
D.60小题4:After class the students often go to _____.
A.their classroom
B.their homes
C.the playground
D.their homes小题5:What may(可能) teachers NOT DO?
A.Give the students lessons.
B.Play football and table tennis with the students.
C.Don’t like some students.
D.Help students study
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