108. News-Why do you get sleepy when you drive

词汇

1. caffeine 咖啡因

2. due to 由于，因为

3. vibration 震动

4. manufacturer 制造商

5. conduct  进行

Why do you get sleepy when you drive?

Most of us have probably felt sleepy on a car journey, but it's not always due to an early start, or a long day, or a lack of caffeine.

It's all to do with the vibrations a car makes as it moves: they can bring on sleepiness in just 15 minutes. That's something for both car manufacturers and road safety experts to think about. They want to conduct further studies into how car seat vibrations could be secretly bringing on sleep.