在信号微机监测系统中，绝缘测试继电器动作靠（）板控制。
A、模入
B、开入
C、模出
D、开出
参考答案：D
. He was so foolish _______ his car unlocked.
A．to leave
B．that leave
C．as to leave
D．for him to leave
农村饮水安全（safe drinking water in rural area）
