When Tom got to the examination room, he realized he ______ his pen at home.
— Could you teach me how _________ cakes? — Sorry, I don’t know.
— How long has Robert __________? — Since 2004.
Mr. Green, a famous writer, __________ our school next week.
—Do you know that band? —Yes. I often watch it ___________ music in the park.
While I __________ with Lily, the school bus came.