1. Tear gas was released as soon as the strikers attacked the riot police. -> Hardly had tear released than the strikers attacked the riot police-đảo ngữ
hardly had+S1+Ved/c4...than S2+Ved/c2
2. The only reason the party was a success was that the Prime Minister attended. -> But for it not been for the attendance of the Prime Minister,the party wouldn't have been a success
But for + Noun Phrases/Ving, S + could/would + Vinf…