The film A World Without Thieves a great success and brought in a large profit to the cinema． A．was enjoyed B．enjoyed C．is enjoyed
鸡蛋壳的主要成分是碳酸钙。为了测定某鸡蛋壳中碳酸钙的质量分数，小群同学进 行了如下实验：将鸡蛋壳洗净、干燥并捣碎后，称取10g放在烧杯里，
在原电池中，较活泼的金属发生 反应，是 极；活动性较差的金属极上发生 反应，是 极。潮湿空气中钢铁表面容
合成橡胶是以___________为原料制成的高分子化合物，具有___________等性能。常用的合成橡胶有___________、___________、___________等。
已知函数 ，方程有6个不同的实数解，则的取值范围是（ ） A． B． C． D．
Recently Peter________to do his homework, and instead insists on wasting his time playing com-puter games, which extremely annoys his father. A. had been refusing B. has been refusing C. w
He has left his book here on _____, so that you can read it. A. purpose B. intention C. aim D. meaning
