They use imperative or bossy verbs, like 'jog on the spot'. If you put a bossy verb at the beginning of a sentence, it turns it into a command. They're usually short, like 'tidy that up', 'stand ...
…Martha is half full. Lenni is less full than Martha, he’s empty. Lenni: Sorry, sorry, it's not funny. Narrator: This is the symbol we use to show that Lenni is ...