The boys arrived late at the cinema,and____the start of the

The boys arrived late at the cinema,and____the start of the film.答案是caught,我觉得是missed,为什
I can't find my pen.Where is it?
Sorry,I don't know.Perhaps you____it home.答案是forgot,我觉得是leave,为什么?
Can I wear any clothes I like to school?
No,you can't.You ____wear a uniform.答案是can,我觉得是must,为什么