In one class,I learned why it rained为什么用rained

In one class,I learned why it rained为什么用rained 短文填词it rained a lot .it was very wet everywhere . class in t It rained---------in most of South China .I stayed at home ( )it rained it rained heavily的heavily 为什么在后面? It rained a lot in summer 还是It rained a lot in the summer? it (rained) all day 对 rained 提问 Tom was late for class because it rained heavily. Yesterday it rained（ ） it rained last night It rained last night. it rained all day