---Look at the boy running on the playground. Is it David? ---It ______ be him. I saw him go to the teachers’ office just now.
-- Have you ever considered _______ Paris some day?
The girl is _______ her mother in many ways. For example, they are both tall and thin.
-- Would you mind carrying the box for me? -- _______
This is the book _______ I have read these years.
Her life ________ a lot during the last three years.