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

He drew two squares on the blackboard.

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

The teacher wrote his name on the blackboard.

The teacher pointed to the blackboard.

The teacher wrote English sentences on the blackboard.

The teacher wrote French words on the blackboard.

I found my name written on the blackboard.

I put on my glasses to see the blackboard.

I had broken my glasses, so that I couldn't see the blackboard.

I'll write it on the blackboard.

Our math teacher drew a circle on the blackboard.

What I can't bear is the sound of chalk squeaking on a chalkboard.

Look at the blackboard.

What did he draw on the blackboard?

Blackboards are not always black.

Written on the blackboard was my name.

I came down from the back to get a better look at the board.

Compare your translation with the one on the blackboard.

Compare your sentence with the one on the blackboard.