“so that” is a conjunction which is used to join two clauses. “so that” is used before the clause which indicates the purpose. Examples. She is too young so that she cannot smoke. It is too late so that we cannot go to cinema. I will go to France so that I can learn French. Let’s go to the cinema early so that we can get good seats. I’m putting the dish in the oven now so that it’ll be ready by eight o’clock.