Question

thanks to those in your life suddenly began to ap

thanks to those in your life suddenly began to appear in due course

Answer 1

对 当一个小男孩和他的父亲正在乡间行走的时候，突然下起大雨来了 对 从句when a small boy and his father were walking in the country；主句it suddenly began to rain hard. 没有这个规定，只有“延续性动词用进行时，结束性动词用一般式”的规律