词汇与结构
Before takeoff, the engines, particularly piston engines, are routinely run up at high power to check for ________ problems.
Before takeoff, the engines, particularly piston engines, are routinely run up at high power to check for ________ problems.
举一反三
- Before takeoff, air hostesses routinely ( ) the<br/>passengers' safety on board. A: check on B: carry on C: concentrate on D: center on
- In some engines, the cylinder_____ also carries the camshaft . A: head B: block C: piston D: port
- In diesel engines， the four basic events (intake， compression， power and exhaust) are performed once in （）.
- With four-stroke engines， it takes four revolutions of the crank shaft to make （） power stroke(s).
- According to the fuel an engine burns, there are ________. A: reciprocating and rotary engines B: gasoline and diesel engines C: 4-cylinder and 6-cylinder engines D: inline and boxer engines