Proposición de planes. Shall

I've left my lunch at home.

Shall I open the window?

Shall we go to the cinema tonight?

What time shall we meet?

Where shall we hace lunch?

I'm sorry but I'm having dinner with my grandparents.

You could buy a sandwich from the canteen.

Yes, please. It's too warm!

There's a new restaurant by the university. Shall we try it?

What about ten o'clock?