The two-stroke cycle begins with the p

1、Hurry up. The lecture begins at 2:00.（

Hurry up. The lecture begins at 2:00.（）ADon‘t worry. We‘ve got 20 minutes.BThank you. No hurry.CNever mind. You go if you like.DThe lecture is useful.

2、In the cylinder head of a two-stroke/c

In the cylinder head of a two-stroke/cycle diesel engine, valves are used for（）Aair intakeBa fuel outletCcooling water inletsDexhausting combustion ga

3、The process of scavenging a two-stroke

The process of scavenging a two-stroke/cycle diesel engine serves to（）Aimprove fuel flow volumeBcool the exhaust valvesCreduce the intake air charge densityDincrease the temperature of exhaust gase

4、The two-stroke cycle begins with the p

The two-stroke cycle begins with the piston coming up from the bottom of its stroke, with scavenge ports in the sides of the cylinder being （）.AshutBclosingCopenedDclosed

5、The four-stroke cycle begins with the

The four-stroke cycle begins with the piston （）.Acoming up from the BDCBcoming up from the TDCCcoming down from the BDCDcoming down from the TDC

6、（）for the Olympic Games begin about te

（）for the Olympic Games begin about ten years in advance.ABidBTo bidCBiddingDTo be bidde