大沟（major groove)和小沟（minor groove)

What led you to select your major？ You minor？

What led you to select your major？ You minor？

What are your major subject and minor subjects？

What are your major subject and minor subjects？

Each journal and pin should be examined for _____ and grooving.A.bridgesB.recessesC.rearsD

Ring groove inserts are occasionally used on aluminum alloy piston to_______.A.reduce the