21. Mid Autumn Day of this year falls on Saturday.
A. The, × B. ×, the C. The, a D. ×, a
22. — What question did the teacher ask just now?
— She asked how well this material electricity or heat.
A. leads B. conducts C. flows D. takes
23. How much has their company this year?
A. brought in B. brought down C. come about D. made in
