1_____there is no rain,farming is difficult or impossible

1_____education is the instruction that occurs when the instructor and students are separated by distance or time,or both

Which do you think is ________, health or wealth？

一台完整的计算机系统由______组成。

29．__________ when you are on the bus or bike．

计算机主机主要由______组成。

计算机的主机由______部件组成。

Which do you think is _________________important, health or wealth?

Duty is an act or a course of action that people __________you to take by social customs, law or religion.

多媒体计算机系统由_______组成。

高级语言的语言处理程序分为解释程序和编译程序两种。编译程序的工作在逻辑上一般由六个阶段组成，而解释程序通常缺少______和代码优化。

计算机的内存储器由______组成。