can be dangerous
That can be dangerous.
Puede ser peligroso caminar solo por esa zona de noche.
It can be dangerous to walk alone in that area at night.
It may be dangerous.
Everything can be dangerous.
Manipular dinamita puede ser peligroso.
Handling dynamite can be dangerous.
Puede ser peligroso conducir durante una tormenta.
Driving during a storm can be dangerous.