Логика такая: нужно раскрыть скобки, поставив глаголы в нужной форме Present Continuous или Present Simple. Внимательно смотрим на контекст.
I'm sitting (sit) in my classroom. We are doing (do) a History test. Paul is writing (write) quickly. Maggie isn't writing (not/write). She is thinking (think) - but she is thinking (think) about the exam or something else? Our teacher is watching (watch) us. He's got a book but he doesn't read (not/read) it. Simon and Will are talking (talk). They aren't trying (not/try) to do the test at all. They don't care. They always do badly in tests. And I'm ... What am I doing (do)? I am wasting (waste) time. Come on, think ... Henry V...