quadro-negro 用英语:

The teacher pointed to the blackboard.

I found my name written on the blackboard.

Take this piece of chalk and write on the blackboard.

He drew two squares on the blackboard.

This blackboard is not black, but green.

I copied in my notebook whatever he wrote on the blackboard.

I'll write it on the blackboard.

Look at the blackboard.

Our math teacher drew a circle on the blackboard.

Compare your sentence with the one on the blackboard.

What did he draw on the blackboard?

The blackboard of the class does not exist anymore.

I put on my glasses to see the blackboard.

Written on the blackboard was my name.

Er, Sir? What's written on the blackboard isn't an exponential function but a trigonometric one ...