Using inversion:I had no sooner launched into my pontification t

Using inversion:
I had no sooner launched into my pontification than I noticed he wasn't listening.
【正确答案】：No sooner had I launched into my pontification than I noticed he wasn't listening.
【题目解析】：No sooner置于句首，主句应采用部分倒装。No sooner… than…，表示“一……就”，引导时间状语从句，主句通常用过去完成时，从句通常用一般过去时。