精子和卵子受精的具体过程是怎样的？

. In that country, the rich ______ richer, the poor, poorer.

A．become

B． has become

C．becomes

D．is becoming

机体排斥微生物侵袭的能力属于下列哪一种免疫功能（）

A.免疫识别

B.免疫防御

C.免疫自稳

D.免疫监视

E.免疫排斥

女性，24岁，贫血1年，血红蛋白80g/L，红细胞3.0×10¹²／L，网织红细胞0.027，白细胞、血小板正常，经用铁剂治疗7天后，血红蛋白不升，网织红细胞0.043。最可靠的诊断是（）

A.铁粒幼细胞性贫血

B.缺铁性贫血

C.营养性巨幼细胞贫血

D.溶血性贫血

E.以上都不是

Which of the following statements is true in the Grammar-Translation Method（）

A. The first language was maintained as the reference system in the acquisition of the second language.

B. The second language was maintained as the reference system in the acquisition of the first language.

C. Latin was maintained as the reference system in the acquisition of the second language.

D. Latin was maintained as the reference system in the acquisition of the first language.

离合器主动件之一飞轮的检查：主要是与（）接触表面磨损情况的检查。

A、主动盘

B、从动盘

C、离合器盖

D、飞轮接盘