有人值守局站油机发电机组应能在市电停电后()分钟内正常启动并供电。
A.15
B.20
C.30
D.40
参考答案:C
Every time _______ I come across difficulties, I will turn to my parents for help.
A./
B.when
C.that
D.which
机动车右转弯时,一般(),两手转动方向盘,左手推送,右手顺势拉动。
A、左手为主,右手为辅
B、右手为主,左手为辅
C、左右手都为主
D、左右手都为辅