Today, let’s look at another way we can express purpose using so that.
To show that one action makes another possible, we say so that + subject + can / could / will be able to / would + verb.
◆ I’m studying English so that I can / will be able to work in America in the future.
◆ He joined a gym so that he could get more exercise.
◆ She bought a guidebook so that she would know where to go sightseeing.
It is usually better to use so that when the subjects are different.
◆ Mark’s parents lent him some money so that he could pay his rent this month.
◆ We put nets over the garbage so that crows won’t be able to tear open the garbage bags.
◆ My wife woke me up early so that I could take out the trash.
To show that an action will prevent something from happening, we can use so that + subject + don’t / won’t / wouldn’t + verb.
◆ Please write this down so that you don’t / won’t forget.
◆ I left home early so that I wouldn’t be late for my appointment.
In casual conversation, native speakers often say so instead of so that.