free practice的用法和样例：
例句
- Thebalance of my car was better than in yesterdays free practice, butstill not perfect for a single timed lap.
我的赛车的平衡性比在昨天的自由练习中要好，但是对于跑单个计时圈来说仍不够理想。 - On Friday, the car was oversteering, but this was caused by a problem in the right, rear shock absorber, which we only found out about after the practice.
周五，赛车转向过渡，但这是由右面的一个问题引起的，是后部的减震器，我们在自由练习后就发现了。
