二百五十多年前的惠更斯目镜今天还在广泛使用.The Huygens ocular , which dates back over 250 years is still in wide use today.此时场镜上的划痕和小点会在接目镜中看见.Then the scratches and spots on the field lens would be visible at the eye lens.在这两种仪器中, 物镜所成的象都是通...
Think carefully before you insure against accident, sickness and redundancy...在为意外事故、疾病与失业投保之前一定要考虑清楚。'One thing you can never insure against is corruption among your staff.'—'Agreed.'“永远也防不胜防的就是员工内部的...
Farming, quarrying and other local industries have declined.农业、采矿业以及其他地方工业都已陷入衰退。Township enterprises in trade , in commerce, mining, coking, quarrying, food service industry.乡镇企业有商贸 、 采煤 、 炼焦 、 采石 、 饮食服务业.In addition, t...