It ___ the students in your class who came to see you then.
Had I known about this computer program, a huge amount of time and energy ________.
If he ________ my advice, he wouldn't have lost his job.
Bob would have helped us yesterday, but he ________.
—I left my handbag on the train, but luckily someone gave it to a railway official. —How unbelievable to get it back! I mean, someone ________ it.(2011·江苏)
—Pity you missed the lecture on nuclear pollution. —I________it, but I was busy preparing for a job interview.(2011·福建)