1. By comparison, relatively little is known about the internal structure of the earth.
    相形之下，对于地球内部结构则了解得较少。

2. We need to have our rotary engine repaired.
    我们需要让人修一下旋转引擎。

3. We felt sure that sooner or later a stone would rip a hole in our petrol tank or damage the engine.
    我们想念迟早会飞起一个石块把油箱砸开一个窟窿，或者把发动机砸坏。

4. That old engine is the archetype of modern locomotives.
    那台老式发动机是近代机车的原形。

5. They started the engine.
    他们开始发动引擎.

6. The steam-engine piston makes a cyclic motion.
    蒸汽机活塞做往复运动。

7. The engine works satisfactorily.
    这引擎性能良好，令人满意。

8. Negro combustion slowly built up to the revolution point.
    黑人的怒火逐渐上升到采取革命行动的地步。

9. He had travelled only seven miles across the Channel when his engine failed and he was forced to land on the sea.
    但他只在海峡上空飞行7英里，引擎就发生了故障，他只好降落在海面上。

10. His engine failed and he landed on the sea for the second time.
    因引擎故障第二次降落在海面上。