下图为高等动物的体内细胞与外界环境的物质交换示意图，下列叙述正确的是( ) A．①③都必须通过消化系统才能完成 B．人体的体液包括内环境和细
下列各句中加点的熟语使用恰当的一句是： A．这几首乐曲是他的早期作品，当然不能和他现在的创作等量齐观。 B．林林自卫失手致人死命，的确有罪
If cars had wings，they could fly and that just might happen, beginning in 2011.The company Terrafugia, based in Woburn, Massachusetts, says it plans to deliver its car-plane, the Transition, to cust
Without proper planning, tourism can cause problems. For example, too many tourists can crowd public places that were also enjoyed by the inhabitants(居民)of a country. If tourists create too much
2010年12月10日至12日，中央经济工作会议在北京举行。会议认真总结今年及“十一五”时期经济工作，科学分析当前国际国内形势，全面部署明年经济工
下面三幅图中，甲图为M地附近地区的平面图，乙图和丙图分别为过甲图相应的点作的地形剖面图。读图回答12--13题。 12．该地区的地形是（ ） A
如图所示，a、b是两个电荷量都为Q的正点电荷。O是它们连线的中点，P、P′是它们连线中垂线上的两个点。从P点由静止释放一个质子，质子将向P′运动
-- Your new bike is very fashionable. -- _________. A．Much better than yours.B．Yes. of course it's very good.C．It's very kind of you to say so.D．No, you are totally wrong~
