关于抗-A抗-B试剂效价正确的是（）。
A.≥32
B.≥64
C.≥128
D.≥216
E.≥512
参考答案：C
A. a; a B. /; / C. /; a D. a; /
用括号内所给动词的适当形式填空.
小题1:When I came into the classroom，Mr．Li (clean)the blackboard．
小题1:
小题2:The boy found a purse (1ie)on the ground and picked it up．
小题2:
小题3:Would you like (have)a try?
小题3:
小题4:Tina hopes she can (invite)to Mary's birthday party．
小题4:
小题5:Mr.Wang finds stamps fascinating．He (collect)them for many years．
小题5:
