Usage of “So and Therefore” and “To and In Order To”

So:

When we want to indicate the result of something, we use “so,” and it’s generally used in the middle of the sentence.

• Maria was listening to music loudly so I warned her.
• She was making noise in the library so I called the librarian.
• He didn’t listen to me so I repeated the topic.
• He was talking to his friend next to him so he couldn’t see the goal.

Therefore:

“Therefore” has the same meaning as “so,” but it’s more commonly used in written language and comes at the beginning of the sentence.

• Maria was listening to the music loudly. Therefore, I warned her.
• She was making noise in the library. Therefore, I called the librarian.
• He didn’t listen to me. Therefore, I repeated the topic.
• The miners didn’t go to work on Monday. Therefore, the director was shocked.

To and In Order To:

We use these to indicate the reason for doing something.

• Last year, I went to the course to learn English.
• I followed him in order to find out what he was doing.
• I called my wife to check the time of the flight.
• We went to the airport in order to meet our friends.
• Selena and I hired a bike to tour the hill.
• I went on a diet to lose weight.
• – Why did you come here?
• – In order to use your phone.