✨ ベストアンサー ✨
1. I would rather watch TV than go shopping.
2. If you are so sleepy, you may as well go to bed.
* may as well のかわりに might as well としても👌
3. You cannot be too careful while (you are) driving.
You cannot be careful enough while (you are) driving.
4. You had better start studying for the examination(s).
* start のかわりに begin でも👌
私が気になって勝手に調べました。なのでこれ以上は分かりません〜
それと、いつも答えてくれるお礼ですw
受験生なのに、わざわざ調べてもらって感激です😭
自分でよければ、答えます〜笑!