这些工人花了三年的时间建筑这座桥梁.（spend on )These workers spent three years on the construction of this bridge. 每年，数以千计的鸟儿飞向南方。（thousands of)Every year, thousands of birds migrate to the South. 请脱下你的外套，并坐下。（take off)Please take off your coat and sit down.那位老师对同学们的学习很满意。（be pleased with )That teacher is pleased with students...
