— Who’s that boy reading in the garden? Is it David?— It ____________ be David. I saw him in the classroom just now.
It is important for us ________English well.
Yesterday the teacher told us that the earth ________around the sun.
________ the alien was in the museum, I called the TV station.
Tim was so tired this morning. It was difficult to _________ of bed.
He told me that he ________ the Disney World the next day.