in order to / so that / so as not to

Rules

• Rule 1: in order to / so as to + base verb

  in order to and so as to are slightly more formal ways to say “to”. They are followed by the base verb, even when the sentence is in the past.

  Pattern: in order to / so as to + base verb

  Example: We left early in order to get good seats.

  Example: She took notes so as to remember the story.

• Rule 2: Negative purpose: in order not to / so as not to

  When we do something so that another thing doesn't happen, not goes right before to.

  Pattern: in order not to / so as not to + base verb

  Example: We walked slowly so as not to spill the water.

  Example: I wrote it down in order not to forget it.

• Rule 3: so that + subject + can / will

  When the purpose has its own subject, use so that + subject + verb. For now or the future, use can / will (or the present simple).

  Pattern: … so that + subject + can / will + base verb

  Example: Speak slowly so that Grandpa can understand.

  Example: I'll set an alarm so that I won't be late.

• Rule 4: so that + could / would in the past

  When the main clause is past and the purpose is also in the past, use could / would.

  Pattern: past tense … so that + subject + could / would + base verb

  Example: Yesterday Mom made pancakes so that we could have a special breakfast.

  Example: Last night I whispered so that I wouldn't wake my sister.

Common mistakes

• I went to the store for buy milk. → I went to the store in order to buy milk.

  For a purpose use to / in order to, not for + verb.

• I spoke loudly in order to everyone could hear. → I spoke loudly so that everyone could hear.

  With a new subject, use so that.

• We whispered not in order to wake the baby. → We whispered in order not to wake the baby.

  not goes right before to.