【单选题】平推流管式反应器,当 t = 时,E(t) =_______。
【单选题】在元宵节之夜有放灯、观灯、赏灯、耍社火、猜灯谜等娱乐活动,所以元宵节又称“灯节”。元宵赏灯始于________。
【多选题】元宵节有( )等娱乐活动,所以元宵节又称“灯节”。
【单选题】He runs so fast that nobody can catch him.
【单选题】He ran so fast that he was out of _____.
【单选题】坐在火车上,对面的乘客请你喝他带的可乐,你觉得哪种做法最妥当?