在室温下，100 ml 0.1mol/L的醋酸溶液中，欲使其溶液的pH减小，但又要使醋酸电离程度减少，应采取（ ）
| A．加入少量CH3COONa固体 | B．通入少量氯化氢气体 |
| C．升高温度 | D．加入少量氢氧化钠固体 |
The children loved their day trip, and they enjoyed the horse ride ______.
| A．most | B．more | C．less | D．little |
Progress______ so far very good and we are sure that the work will be finished on time.
| A．was | B．had been | C．has been | D．will be |
Charles was alone at home, with_______ looking after him.
| A．someone | B．anyone | C．not one | D．no one |
It is often ______ that human beings are naturally equipped to speak.
| A．said | B．to say | C．saying | D．being said |
I can’t leave. She told me that I ______ stay here until she comes back.
| A．can | B．must | C．will | D．may |