"Close metal-to metal fit of all parts forms the basic seal." in above sentence,"Close metal-to metal fit" means "金属和金属的紧密结合".
A.1
正确答案是A
"Close metal-to metal fit of all parts forms the basic seal." in above sentence,"Close metal-to metal fit" means "金属和金属的紧密结合".
A.1
正确答案是A