【单选题】Which idiom means when you need to decline an invitation, but you want to reschedule it for the future.
【单选题】在显微镜的低倍镜下看到一个细胞偏向左上方,在换高倍镜观察前应该把该细胞移到视野中央,具体作法是:
【单选题】在显微镜的低倍镜下看到一个细胞偏向左上方,在换高倍镜观察前应该把该细胞移到视野中央,具体说法是
【单选题】______ is an idiom, which means to make appeals in vain.
【单选题】“ 龙虎斗 ” 是纳西族人治疗 的秘方。
【判断题】There is an English idiom” to carry coal to Newcastle”, which means to help somebody in time.