Infinitives as Adverbials

Infinitives (to + the simple form of the verb) can be used to answer the question Why? They let us know the purpose of an action.

smile braces teeth mouth person face girl woman infinitives grammar ESL EnglishWhy did she get braces? She got braces to straighten her teeth.

Why did she want to straighten her teeth? She wanted to straighten them to have a nicer smile.

(You can use “in order to” or “so as to”+ the simple form of the verb, but the infinitive alone does the same job just as well.)

She got braces in order to straighten her teeth. She wanted to straighten them in order to have a nicer smile.

wolf fairy tale red riding hood girl illustration story book picture child infinitives ESL English grammar Why did the wolf dress up like Little Red Riding Hood’s grandma?

He did it to hide who he really was. He did it to trick Little Red Riding Hood. He did it to eat her up.

van gough painter artist painting art selfie smart phone camera apple iphone infinitive English ESL grammar Why did Van Gogh take a selfie?

He did it to be cool. He did it to post to instagram.

To make the infinitive negative, just add “not” in front of it.

motorcycle bike dirtbike stuntbike stunt dirt ride fast danger daredevil infinitive sport hobby English grammar ESL Why did the bike rider wear protective gear?

He did it not to get injured. He did it not to hurt himself. He did it so as not to break any bones. He did it in order not to get in trouble with his mom.

Practice: Answer these questions using a (+) or a (-) infinitive. Practice using the more formal “in order” or “so as” in front of the infinitive as well.  Some possible answers follow.
  1. Why did you get a car alarm?
  2. Why do you take vitamins?
  3. Why do you work out?
  4. Why do you sometimes ignore text messages?
  5. Why do you post cool pictures on Instagram?
  6. Why do you read the news?

Possible answers:

  1. I got one so as not to be the victim of a car prowl.
  2. I take them to stay healthy.
  3. I work out to stay in shape. I work out in order not to feel stressed.
  4. I ignore them to have more privacy. I ignore them not to be bothered.
  5. I post cool pictures to get my friends to envy me. I post cool pictures so as not to forget things I have done.
  6. I read the news in order to stay informed. I read the news so as not to be ignorant.