It's the difference between first watching an experienced mechanic, and then haphazardly trying to wing rebuilding an engine.

这就是与第一次看完一位熟练的技工操作，然后自己胡乱去重组一台机械不同之处。

youdao

And there is always a mechanic on stand-by at the back of the car with a power-operated engine starter, ready for instant use if the car stalls.

在赛车尾部总有一个技师手持引擎启动器，随时准备防止赛车熄火。

youdao

The mechanic straightened up, wiped his hands on a rag and said, "So Doc, look at this engine.

机械师挺直腰板，在抹布上擦了擦手，对他说道：“呃...您看看这个引擎。

youdao

He's also experienced an engine-part failure that a mechanic blamed on ethanol, but he said he's sure there were other issues that caused the shutdown.

CNN: Ethanol: Is it friend or foe?

Should the family of an experienced motor mechanic who asphyxiated himself by running a car engine in his garage be entitled to cash from the manufacturer of a muffler-repair kit?

FORBES: Who Knew That Carbon Monoxide Kills?

Hiding behind the petrol pumps, viewers could watch the astonishment of a mechanic as he discovered that the car Mr Routh had coasted into the garage contained no engine neither under the bonnet, nor under the chassis, nor in the boot.

ECONOMIST: Jonathan Routh