They regret that Tom couldn't catch Jerry.
⇒ They wish Tom could have caught Jerry
Khẳng định: S + wish(es) + (that) + S + would/could + V
Phủ định: S + wish(es) + (that) + S + would/could + not + V
Cấu trúc If only: S + wish(es) + (that) + S + would/could + (not) + V