1. concentrated (it's time+S+V-lùi thì)
2. It is necessary that he come to the interview early (It is necessary+S+V-bare+...)
3. Were I not broke, I could lend you money (cấu trúc đảo ngữ câu đk loại 2: Were+S+adj/to V+..., S+could/would/...+V-bare+...)