— Who’s that boy reading in the garden? Is it David?— It ____________ be David. I saw him in the classroom just now.
Joe’s schoolbag is differentTony’s but similarLisa’s.
--_____? --For tow hours.
Nanjing is one of thein China.
The college entrance examination(the gaokao)is one of the most important exams.Families take it_____.
Cindy is always helpul. She only thinks of others and does not_____herself.