题目

英语翻译
1)Proper drainage is essential in road building,because if the foundation became soggy,the heavy road would sick into it.And if the water were to freeze in the ground,it would expand and crack the road.To protect the highway from such damage,drainpipes called culverts are laid across the roadbed wherever a strong flow of water is expected.the roadbed itself is shaped so that the middle of the finished road would be higher than the sides.Then water and melting snow will easily drain off its surface into the drainpipes or ditches.The roadbed is given a final grading(smoothing) and is now ready to receive the road itself.
2)A bridge has always offered man the satisfaction of successfully conquering an obstruction,be it a primitive bridge of the ancients or a modern bridge of immense gracefuk in view,balanced in distribution of mass,harmonious in proportion,orderly in lines,integral with the environment.
3)In ancient times,bridges often crossed rivers at right angles,had h

提问时间：2021-02-07

答案