Read the following passage carefully and fill in each blank with a proper word from the list. backbone reciprocating handles various large piston crankshaft counterbalanced weight rotary serves The ( 1), regarded as the"( 2)"of the engine, ( 3) to change the(4) motion of the piston into ( 5) motion and ( 6) the entire power output. The crankshaft is actually made up of (7)parts such as main bearing journal, rod journal, crank arm, ( 8) and flywheel. The connecting rod links its (9)end to the crankshaft and its small end to the (10)