化学中常借助曲线图来表示某种变化过程，有关下列四个曲线图的说法正确的是
| A．曲线图①可以表示对某化学平衡体系改变温度后反应速率随时间的变化 |
| B．曲线图②可以表示向一定量的氢氧化钠溶液中滴加一定浓度的稀硫酸时pH变化 |
| C．曲线图③可以表示相同pH的CH3COOH和HCl溶液分别加水稀释时溶液的pH随溶液体积变化的曲线 |
| D．曲线图④可以表示所有的固体物质溶解度随温度的变化 |
My friend showed me round the town, ______ was very kind of him. 
| A．which | B．that | C．where | D．it |
They use computers to keep the traffic _______ smoothly.
| A．being run | B．run | C．to run | D．running |
If you leave the club, you will not be_____back in .
| A．received | B．admitted | C．turned | D．moved |
What I need is_____ book that contains ______ABC of oil painting.
| A．a; 不填 | B．the; 不填 | C．the; an | D．a ; the |
Jenny nearly missed the flight______ doing too much shopping.
| A．as a result of | B．on top of | C．in front of | D．in need of |