21. My brother asked me to go for ____walk, but I don’t think I have got _____energy.
A. a, / B. the, the C. /, the D. a, the
22. By the time he arrives in Beijing, we _____here for two days.
A. will have stayed B will be staying C have been staying D have stayed
23. When this happens, he smiles and nods, ____ that everything is fine.
A. indicated B. indicating C. to indicate D. indicate
