下列说法正确的是
| A.SO2和NO2都是酸性氧化物,都能与水反应生成酸 |
| B.Na2O和Na2O2组成元素相同,与CO2反应产物也完全相同 |
| C.Al2O3和Na2O按物质的量比1:1投人水中可得到澄清溶液 |
| D.金属铝排在金属活动性顺序表中氢元素的前面,铝与强酸反应一定放出氢气 |
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 |
The CDs are on sale! Buy one and you get ______ completely free.
| A.other | B.others | C.one | D.ones ks |