A:2NaHCO3 △_ Na2CO3+CO2↑+H2O
B:H2SO4+CuO═CuSO4+H2O
C:2 H2S+SO2═3S↓+2H2O
D:CO2+Ca(OH)2═CaCO3↓+H2O
— Did you listen to Li Yundi _____ the piano yesterday evening?
— Yes. He played _____ and all the audience clapped loudly at the end.