一个男子把X染色体上的基因传递给孙子的几率为[ ]
A.l/8
B.1/4
C.0
D.1/2
答案:C
The doctor told him that ____ was necessary to take the medicine on time. [ ]
A. that
B. it
C. this
D. what
新安装的砌有砖墙的锅炉,其墙灰缝内含有大量的水分,要使其干燥硬化,需对锅炉进行。()
A、煮炉
B、烘炉
C、停炉