Zdania warunkowe (zero conditional)
1. If you press this button, the lights come on.
2. If you can't say anything nice, don't say anything at all.
3. I'm here if you need me.
4. If I drink coffee in the evening, I never sleep well.
5. If you say "sit", my dog sits down.

Zdania z should/shouldn't
1. I shouldn't watch so much TV.
2. I should help my mother in the kitchen.
3. They should be happy - they have won!
4. We shouldn't cry on her wedding.
5. You should listen to the teachers.