—Who______ it be that is knocking at the door? —It ______ be Father, but I’m not sure.
Unsatisfied ______with the payment ,he took the job just to get some work experience.
—Hi, Tom . Any idea where Jane is?—She _____in the classroom . I saw her there just now.
We should consider the students’ request ___the school library provide more books on popular science.
Professor Williams keeps telling his students that the future ______to the well-educated.
With the world changing fast, we have something new _______with all by ourselves every day.