开车时使用手机会导致严重事故。

Using a mobile phone while driving can ___cause serious accidents.

专家表示，过多的社交媒体可能会导致青少年焦虑。

The expert said that too much social media might ___cause anxiety in teenagers.

准备不足导致他考试表现不佳。

His lack of preparation ___caused him to perform poorly in the exam.