Cepheid variable stars are stars whose brightness changes at regular periods.造父变星是一种光线按规律周期发生变化的恒星.His first great discovery was made when he recognized a Cepheid variable star.他的首次重大发现产生于他认识了一颗造父变星的时候....
吃过晚饭，尼娜和玛丽在厨房里收拾。Nina and Mary were in the kitchen, cleaning up after dinner.他得为尼娜付一大笔私立学校的学费。He will have to fork out for private school fees for Nina.尼娜无法将她的视线从菲利普身上移开。Nina couldn't take her eyes off Philip....
传送带下沉重的钢滚筒the heavy steel rollers under the conveyor belt这个大齿轮带动小齿轮使滚筒旋转.This large gear turns the small one to rotate the cylinder.粉碎辊是波纹式滚筒, 还常是螺旋割纹式.These rolls are corrugated cylinders, usually of the spiral type....
Few officers thought that a German-Czech war could be localized.没几个军官认为德捷之战可被控制为局部战争。Fish populations assume highly localized distributions within each river.鱼群分布集中在每条河的某些区域.She had localized breast cancer and both of he...