Mark tried to tie the boat to the buoy so that______.
A. he could spend the night on it while John was looking for help
B. he and John could go sailing again when the fog cleared
C. they would be safer
______Lily______ I have been to the Great wall.
A. Either; or
B. Neither; nor
C. Both; and
下列关于打印机的叙述,不正确的是______。
A. 打印机有两条线,一条是电源线,另一条是信号线
B. 并行打印机的信号线连接/拔出不必关闭系统
C. USB接口打印机的信号线连接/拔出不必关闭系统
D. 安装打印机,就是为打印机安装驱动程序
Do the trains always run______
A. on time
B. in time
C. the same time