We use 'prevent' to say that something stops a bad event or action before it starts. It means making sure something does not happen.
They prevent accidents with safety rules.
I prevent cold by wearing warm clothes.
Here 'prevent' means stopping someone from going into a place or taking part in something. It is about not allowing or blocking someone.
They prevent people from entering the club.
The guard prevents him from going inside.
'Prevent' in health means to stop illness or harm before it starts. People try to avoid bad things by acting early.
Vaccines prevent many diseases worldwide.
Good sleep can prevent health problems.
'Prevent' here means to stop progress or development. Something stops a plan or idea from moving forward.
High costs prevent the project from growing.
Fear prevented her from trying new things.
This use of 'prevent' is to stop something from coming close or touching something else by using a tool or method.
The fence prevents animals from entering.
Rain jackets prevent water from soaking you.
'Prevent' is used formally with laws or rules to mean not allow certain actions by order or law.
The law prevents smoking in public places.
Rules prevent students from cheating.