1. When surveyors sight the summit, there is a risk they might not all measure the same point. 当测量员们看到山顶时，他们可能无法测量到同一个点。
2. To measure the difference in elevation between poles, surveyors used an optical level—a telescope on a level base—placed halfway between the poles. 为了测量两极之间的高程差，测量员在两极中间的一个水平基座上使用了光学水准望远镜。
3. The companies building the canals to transport coal needed surveyors to help them find the coal deposits worth mining as well as to determine the best courses for the canals. 修建运河运输煤炭的公司需要测量员帮助他们找到值得开采的煤矿，并确定运河的最佳路线。
4. Surveyors marched inland from the coast for thousands of miles, stopping at increments of as little as a few feet to measure their elevation, and marking each increment with two poles. 测量员从海岸向内陆行进数千英里，每增加几英尺就停下来测量海拔，每增加一英尺就用两根杆子做标记。
5. Surveyors carried out a valuation of the property. 鉴定人员对这处房产做了估价。
