在对电子运动状态的描述中,确定一个“轨道”的方面包括①电子层 ②电子亚层 ③电子云的伸展方向 ④电子的自旋状态
The children loved their day trip, and they enjoyed the horse ride ______.
Progress______ so far very good and we are sure that the work will be finished on time.
Charles was alone at home, with_______ looking after him.
It is often ______ that human beings are naturally equipped to speak.