例句與造句

1. Fixed roller dams are generally made from reinforced concrete or masonry.
2. Roller dams of any type pose an extreme drowning hazard.
3. Roller dams can be either fixed ( non-moving ) or active.
4. Because of the hazards, dam opponents have called for the removal of roller dams.
5. Active roller dams are a German invention stolen by the U . S . during World War 1.
6. It's difficult to find roller dam in a sentence. 用roller dam造句挺難的
7. Sixteen people have died by drowning at the roller dam on the Cedar River in Cedar Rapids, Iowa.
8. A roller dam is a type of dam that is designed to allow water to constantly spill over its top.
9. Active roller dams are made out of large metal cylinders that can be lifted out of the water using a system of powerful hydraulic rams.
10. Active roller dams are made from large metal cylinders, which can be lifted out of the water using a system of powerful hydraulic rams or cables and motors.
11. Lock and Dam No . 15, completed in 1934 as a federal Works Progress Administration ( WPA ) project during the Great Depression, is the largest roller dam in the world.
12. As the water pouring over the dam hits this wall it is reflected back toward the dam face creating a continual " rolling " action at the bottom of the dam; hence the name " Roller Dam ".