This time we're looking at the difference between 'prevent' and 'avoid'.

'Prevent' basically means 'stop'.

If you prevent something, you stop it from happening - often before it starts.

You can prevent something, prevent something from happening or prevent someone from doing something.

For example: The arrival of the police prevented crime.

Or: Losing my passport prevented me from flying.

Or: I prevented her from slapping me! Wow!

Now 'avoid', basically means 'miss'.

If you avoid something, you try to make it miss you.

For example: I avoided meeting my ex.

Or: I avoided the slap easily!