What do the police think about the murder?— I’m not sure. But I want anyone who ______ the clue to contact the police actively.

It took _________ people _________ the work.

Ann, _____ the lights when you leave the classroom.

I had _________ entered the classroom when I noticed the headmaster was sitting at the back.

Spring has come. We can’t____ the plan. The trees must be planted this week.