在一个6L的密闭容器中，放入3LX（气）和2LY（气），在一定条件下发生下列反应：4X(g) + 3Y(g) 
2Q(g) + nR(g)，达到平衡后，容器内温度不变，混合气体的压强比原来增加5%，X的浓度减小1/3，则方程式中n值（ ）
| A．3 | B．4 | C．5 | D．6 |
It is often ______ that human beings are naturally equipped to speak.
| A．said | B．to say | C．saying | D．being said |
I’m sure that your letter will get______ attention. They know you’re waiting for the reply. 
| A．continued | B．immediate | C．careful | D．general |
All the dishes in this menu, ______ otherwise stated, will serve two to three people. 
| A．as | B．if | C．though | D．unless |
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 |