Expressing Purpose

2nd Year Bac · Unit 3 · Functions

Learn to explain WHY someone does something — with to, in order to, so as to, and so that — the exam's favourite sentence-rewriting topic.

What is 'purpose'?

Purpose means the reason behind an action — the “why” of a sentence. “She woke up early to catch the bus” tells us not just what she did, but why. This function appears constantly in the exam, especially in sentence-rewriting exercises.

ما معنى “الغرض” (Purpose)؟
الغرض يعني السبب وراء فعل ما — “لماذا” في الجملة. “استيقظت باكرًا لتلحق بالحافلة” لا تخبرنا فقط بما فعلته، بل تشرح السبب. هذه الوظيفة تظهر كثيرًا في الامتحان، خصوصًا في تمارين إعادة الصياغة.

Same subject: to / in order to / so as to

When the same person does both actions, use one of these three, followed by the base verb.

Same-subject purpose

toin order toso as to

Example

He joined a language centre to learn English.
He joined a language centre in order to learn English.
He joined a language centre so as to learn English.

💡 Good to know

All three sentences above mean exactly the same thing. “To” is the simplest and most common; “in order to” and “so as to” are slightly more formal — useful for essays and formal writing.

Different subject or a modal: so that / in order that

Use so that or in order that + subject + a modal verb (can, could, will, would) when the subject of the purpose changes, or when you want to include a modal.

Formula

so that / in order that + subject + modal verb. She saved money so that she could buy a car.

Example — different subject

The teacher spoke slowly so that the students could understand. (the teacher speaks, but the students understand — two different subjects)

Example — same subject, but with a modal

He exercises regularly so that he will not get obese.

Negative purpose

To explain that someone does something to avoid a result, use so as not to or in order not to + base verb.

Example

She woke up early so as not to be late for school.
He joined a gym in order not to get fat.

⚠️ Watch out

The negative goes before “to”, not after: ❌ so as to not be late → ✅ so as not to be late.

See it side by side

Same subject

She left early to catch the bus.

He studies hard in order to succeed.

They saved money so as to travel abroad.

Different subject / with a modal

She whispered so that she wouldn’t wake the baby.

He locked the door so that no one could get in.

I gave him my number so that he could call me.

Common mistakes to avoid

⚠️ Watch out

❌ She left early for catch the bus. → ✅ She left early to catch the bus. (“for” is not followed by a base verb this way)

❌ He studies hard so that pass the exam. → ✅ He studies hard so that he can pass the exam. (so that needs a subject + modal)

❌ They trained so as winning the match. → ✅ They trained so as to win the match. (base verb, not -ing)

✏️

Your turn — choose the correct form

1. She left early ___ the bus.
2. He studies hard ___ the exam.
3. They trained hard ___ the match.
4. She whispered ___ wake the baby.
5. The teacher spoke slowly ___ the students could understand.
6. I saved money ___ a car.
7. He joined a gym ___ get fat.
8. Choose the correct sentence.
9. “So that” is usually followed by a subject and a ___.
10. She gave him her number ___ he could call her.
11. Which shows the SAME subject in both parts?
12. Choose the correct sentence.

✏️ Sentence rewriting ✍️

Rewrite each sentence using the purpose expression given in brackets:

She wants to pass the exam. She studies every night. (in order to)
He didn’t want to be late. He woke up early. (so as not to)
The teacher wants her students to understand. She explains slowly. (so that)
I want to save electricity. I turn off the lights. (to)
He doesn’t want to get fat. He goes to the gym. (in order not to)

Watch: Expressing Purpose

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Expressing Purpose — 2 Bac Grammar Functions