微机系统常用的打印机有机械式打印机、喷墨式打印机、激光式打印机三种。（√）115、1KB表示1024字节。
参考答案：对
We should love our oceans and do something to them .
A．plant
B．find
C．harm
D．protect
Ordinary people are now lacking of the scientific knowledge about nutrition.
A．short with
B．are absent of
C．lack in
D．are deficient on
