非等位基因

Can you learn English ________ chatting on the Internet?

A．in

B．with

C．by

D．for

Could you give me a hand?It seems that my strength has________. [ ]

A . used up  

B. run out

C. been given out  

D. run out of

用钢圈连接的水泥杆，在焊接时应遵守哪些规定？

下面哪些有关血友病的描述是错误的：（）

A.血友病A较为常见

B.血友病A是常染色体不完全隐性遗传

C.血友病C由女性传递，男性发病

D.血友病B两性都可发病

E.血友病C出血较严重

专利权