When you want to say the goal of an action — what you do it for — English often uses a simple pattern: to + the base verb. I went to the shop to buy milk. That little to + verb answers the question Why?

This is called the infinitive of purpose. It's one of the most useful patterns at this level, because it lets you join an action to its goal in a single, natural sentence. (For a cause or explanation rather than a goal, English usually uses because: I stayed home because I was ill — not ❌ to be ill.)

Quick shortcut: if you can answer with "in order to…", use to + verb — not for. I came here to learn English (✅), not ❌ I came here for learn English.

The basic pattern: to + verb

To explain the purpose of an action, add to + the base form of the verb:

  • I'm saving money to buy a car.
  • She went outside to make a phone call.
  • We stopped to rest for a few minutes.
  • He's learning English to get a better job.

The first part is the action; the to-part is the goal behind it. After this infinitive to, the verb stays in its base form — to buy, to pass, to get — never to buying, never to bought.

Usually the person who does the first action also does the goal action: I went outside to make a call means I made the call. When someone else does the second action, English tends to use another structure instead: I opened the door so that he could come in.

Answering Why?

When the answer is a goal or intention, the infinitive of purpose is a natural way to answer a why question:

  • Why did you call me? — To invite you to my party.
  • Why are you studying so hard? — To pass my exam.
  • Why did she go to the station? — To meet a friend.

You can give the whole sentence (I called you to invite you…) or just the to-phrase as a short answer (To invite you). Both are correct.

to, in order to, so as to

At this level, plain to is the main pattern. For a slightly more formal version, you'll also meet in order to and so as to, which mean exactly the same:

  • I left early to catch the train.
  • I left early in order to catch the train.
  • I left early so as to catch the train. (more formal — useful mainly to recognise)

In everyday speech, plain to is by far the most common. In order to is more formal, and so as to is more formal still.

For a negative goal ("so that something does not happen"), the clearest forms are in order not to or so as not to:

  • I wrote it down so as not to forget.
  • She spoke quietly in order not to wake the baby.

An easy A2-friendly alternative is to use because + a negative: She spoke quietly because she didn't want to wake the baby.

to + verb vs for + noun

Here's the part that trips most learners up. In this purpose pattern:

  • Before a base verb, the choice is to: I went to the shop to buy bread.
  • Before a noun, the choice is for: I went to the shop for some bread.

So for is fine — but in this pattern it goes in front of a noun, never in front of a base verb:

  • ✅ I came here to study English. ❌ I came here for study English.
  • ✅ I came here for an English course. (noun → for is correct)

One thing to keep separate: for + -ing does exist, but for a different idea — describing what something is used for: This knife is for cutting bread. That's the use of an object, not the goal of a person's action, so it doesn't replace to + verb. A useful test for purpose: if a person's goal comes next as an action, it's to + verb.

Common mistakes

  • ❌ I went out for buy milk. → ✅ I went out to buy milk. (purpose before a verb → to)
  • ❌ I came here for to learn English. → ✅ I came here to learn English. (no for before to)
  • ❌ She called me for invite me. → ✅ She called me to invite me.
  • ❌ He studies hard to passing the exam. → ✅ He studies hard to pass the exam. (base form after to)
  • ❌ I closed the door for not to wake the baby. → ✅ I closed the door so as not to wake the baby.

Quick check

Complete each sentence with to + verb or for + noun:

  1. I'm going to the library ____ ____ (study).
  2. We stopped at a café ____ a coffee. (a noun follows)
  3. Why did you phone her? — ____ ____ (say) thank you.
  4. He's saving up ____ ____ (buy) a new phone.
Show answers
  1. to study   2. for (a coffee)   3. To say   4. to buy

Key takeaways

  • To explain why you do something, use to + the base verb: I called to invite you.
  • It's the natural answer to a why question.
  • In order to and so as to mean the same as to, just more formal; for the negative, use in order not to / so as not to.
  • Use to before a verb, but for before a noun: ✅ to buy bread, ✅ for some bread, never ❌ for buy bread or ❌ for to buy.