关于no sooner thanNo sooner (had) I got into classroom than the bell ring用不用加had?那如果不加had ring 用不用变为rang?

一定要加had；原句中的ring要变成rang
英语中有几个表示“一。。。就。。。”的结构：主句都用过去完成时，从句用一般过去时：
I had no sooner got into classroom than the bell rang.
No sooner提前句子倒装：
No sooner had I got into classroom than the bell rang.
I had hardly got into classroom when the bell rang.
Hardly提前句子倒装
Hardly had I got into classroom when the bell rang.
I had scarcely got into classroom when the bell rang.
scarcely提前句子倒装
Scaecely had I got into classroom when the bell rang.

你这语法不对啊 引导时间状语从句,主句用过去完成时,"than"后面的从句用一般过去时
no sooner 提前句子要半倒装，你这句子的时态也不对。
应该是：No sooner had I got into classroom than the bell rang

加had同时还要把ring变为rang
no sooner +过去完成时..than + 过去时