sill cock造句

• All outlets including sill cocks must be downstream of the model 7
  所有出口，包括洒水龙头，必须位于型号7的下游。
• Models 8a , 8b , 8fr and 8p hose connection vacuum breakers are constructed to allow sill cocks to be drained
  型号8a , 8b , 8fr和8p软管连接真空断路阀其结构允许洒水龙头排放。