护士采集张先生的痰标本作细胞学检查，目的是为了确定痰中是否有
A．红细胞
B．黏液管型
C．癌细胞
D．致病菌
E．白细胞
参考答案：C
My pen pal from America is coming to visit me . I’m thinking about ______________.
A．What present did I give her
B．how I will give her a surprise
C．where will we have a big meal
D．whether I planned a trip for her
不属于低溶解性氟化物的是
A．CaF2
B．MgF2
C．AlF3
D．NaF
E．以上均是
