计算机系统中的硬件系统包括主机和外设。下面关于主机正确的说法是______。

Many boys enjoy _______ football, basketball or baseball

－ What does the sign over there read － “No person ________ smoke or carry a lighted cigarette, cigar or pipe in this area”

Which do you think is ________, health or wealth？

下面，关于计算机安全属性说法不正确的是____。

下面关于计算机病毒说法正确的是____。

下面关于系统还原说法正确的是______。

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

下列关于计算机系统硬件的说法中，正确的是______。

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

下面关于计算机病毒说法不正确的是______。

下面关于计算机病毒说法正确的是_____。