valve-rocker arm cover

例句：

1. 1.The valve rocker arm cover is designed to protect the valve from damage during operation.
   阀门摇臂护罩的设计目的是在操作过程中保护阀门不受损害。
2. 2. The engineers carefully inspected the valve rocker arm cover before installing it in the machine.
   工程师们在安装机器之前仔细检查了阀门摇臂护罩。
3. 3. The valve rocker arm cover was replaced after a few months of use, as it had become damaged.
   在使用几个月后，阀门摇臂护罩被更换了，因为它已经损坏了。