3. 怎样学会使用这个词？
1）翻译下面的句子：
过去几年投资是中国经济的引擎，现在主要是消费在拉动中国经济。
（参考翻译：While investment was the engine of China's economy a few years ago, today it's mainly driven by consumption. 或 In the past few years, China's economy was driven mainly by investment, whereas today its engine is consumption.）
2）结合自己的生活、学习、工作、兴趣等，想象在什么语境下会用到这个表达。先简要描述这个场景，再造句。
A good relationship is the engine of a happy family life.
