check ball的相关资料：
临近单词
checkrow
check
checking and evaluating indexes system
Check/correct flywheel alignment.
Checking the Capacitor on Distributors
check alteration and forgery insurance
Checking Over-center Rotation Torque
Check construction quality by level.
Checking of the mechanical governor.
Checking what files need installing.
Checking test of special-shape steel
Check the manuscripts over carefully.
