"Expressing Purpose (pour que, afin que)" → "Expressing purpose: 'pour que' / 'afin que' = 'so that' / 'in order that' (use subjunctive); 'pour' / 'afin de' = 'to' / 'in order to' (use infinitive)"

Expressing Purpose in French: pour que, afin que (so that / in order that)

What does "expressing purpose" mean?

Expressing purpose answers the question Why? — it explains the goal or intended result of an action. In English we use "to" / "in order to" (infinitive) or "so that" / "in order that" (subordinate clause). In French, common ways to express purpose include:

- pour + infinitive (same subject) — Je travaille pour réussir. (I work to succeed.)
- afin de + infinitive (formal, same subject) — Elle étudie afin d'obtenir une bourse. (She studies in order to get a scholarship.)
- pour que / afin que + subjunctive (different subject) — Je parle doucement pour que bébé puisse dormir. (I speak quietly so that the baby can sleep.)

When do I use pour/afin de (infinitive) vs pour que/afin que + subjunctive?

- Use pour + infinitive or afin de + infinitive when the subject of the main clause and the purpose (infinitive) is the same person or thing.
- Example: Je me lève tôt pour courir. (I get up early to run.) — subject is "je" in both parts.

- Use pour que + subjunctive or afin que + subjunctive when the purpose clause has a different subject from the main clause (or when you need a full clause introduced by "que").
- Example: Je me lève tôt pour que mon frère puisse prendre le bus. (I get up early so that my brother can catch the bus.) — different subjects: "je" vs "mon frère".

Note: "afin de" is followed by an infinitive, while "afin que" is followed by a subjunctive clause — they are not interchangeable with the same form.
- Correct: Il travaille afin d'obtenir une promotion.
- Correct: Il travaille afin qu'il obtienne une promotion.
- Incorrect: Il travaille afin que obtenir une promotion.

Why is the subjunctive used after pour que / afin que?

The subjunctive mood expresses desire, intention, uncertainty or something that is not yet realized — exactly what a purpose clause does: it expresses an intended or desired outcome, not a factual statement. So after "pour que" and "afin que" the verb is usually in the subjunctive.

Example with present subjunctive:
- Je t'explique lentement pour que tu comprennes. (I explain slowly so that you understand — "comprennes" = subjunctive)
- Il a baissé la musique pour que les voisins puissent dormir. (He turned the music down so the neighbors can sleep — "puissent" = subjunctive)

How is the present subjunctive formed (briefly)?

A quick formation rule for the present subjunctive (regular verbs): take the 3rd person plural of the present indicative, drop -ent and add endings -e, -es, -e, -ions, -iez, -ent. There are irregular verbs you should memorize (être, avoir, aller, faire, pouvoir, savoir, vouloir, etc.).

Key irregular subjunctive forms to know:
- être -> que je sois, que tu sois, qu'il/elle soit, que nous soyons...
- avoir -> que j'aie, que tu aies, qu'il ait, que nous ayons...
- pouvoir -> que je puisse, que tu puisses, qu'il puisse, que nous puissions...
- aller -> que j'aille, que tu ailles, qu'il aille, que nous allions...

Other connectors that express purpose

Apart from pour/afin, French has several alternatives:

- dans le but de + infinitive (formal): Il a agi dans le but de protéger sa famille. (He acted with the aim of protecting his family.)
- en vue de + infinitive: Ils économisent en vue d'acheter une maison. (They are saving to buy a house.)
- de façon à + infinitive (same subject): J'ai rangé la maison de façon à faciliter le nettoyage. (I tidied the house so as to make cleaning easier.)
- de façon à ce que / de manière à ce que + subjunctive (different subject): J'ai arrangé les chaises de façon à ce que tout le monde puisse voir. (I arranged the chairs so everyone could see.)
- de sorte que / de telle sorte que: can be used for purpose (subjunctive) or result (indicative). See next section.
- pour éviter de / pour éviter que + subjunctive: Je l'ai éteint pour éviter de le déranger. / Je l'ai éteint pour éviter qu'il ne se réveille.

Purpose vs Result: de sorte que, de façon que, de manière que

Some connectors (de sorte que, de façon que, de manière que) can express either purpose or result:
- If they express purpose (intention), they are followed by the subjunctive.
- Purpose: Il a baissé la voix de sorte que les enfants puissent dormir. (He lowered his voice so that the children can sleep.) — "puissent" = subjunctive.
- If they express a result (what happened), they are followed by the indicative.
- Result: Il a baissé la voix, de sorte que les enfants ont dormi. (He lowered his voice, so the children slept.) — indicative.

Tip: Ask yourself: Is this the intended goal (use subjunctive)? Or am I stating an actual outcome (use indicative)?

Negation in purpose clauses

To express a negative purpose ("so that ... not"), use "ne ... pas" in the subordinate clause. With "pour que" or "afin que" the subordinate clause still takes the subjunctive when needed.

Examples:
- Je parle doucement pour que le bébé ne se réveille pas. (I speak quietly so the baby won't wake up.)
- Il a fermé la fenêtre afin qu'on n'entende pas le bruit. (He closed the window so we wouldn't hear the noise.)

Note: Some verbs and constructions use an "expletive ne" (a "ne" that doesn't make the sentence negative) after verbs of fear or expressions like "de peur que / de crainte que" — e.g. "Elle est sortie tôt de peur qu'il ne pleuve." This is a separate topic but common in negative-purpose-like clauses.

Common mistakes and how to avoid them

- Mistake: Using "pour que" when the subject is the same. Wrong: *Je vais au gymnase pour que rester en forme.*
- Correct: Je vais au gymnase pour rester en forme.

- Mistake: Using indicative after "pour que". Wrong: *Je te le dis pour que tu sais la vérité.*
- Correct: Je te le dis pour que tu saches la vérité. (subjunctive)

- Mistake: Mixing "afin de" and "afin que" forms. Wrong: *Il étudie afin que réussir.*
- Correct: Il étudie afin de réussir. (same subject, infinitive) or Il étudie afin qu'il réussisse. (different subject, subjunctive)

- Mistake: Using "pour que" when "pour + infinitive" is needed. Check the subject of the action after "to/for": if it's the same person, prefer the infinitive.

Comprehensive examples by pattern

Same subject: pour + infinitive / afin de + infinitive / dans le but de + infinitive
- Je travaille pour gagner de l'argent. (I work to earn money.)
- Elle étudie afin d'obtenir une bourse. (She studies in order to get a scholarship.)
- Nous économisons dans le but d'acheter une maison. (We are saving with the aim of buying a house.)
- Il a éteint son téléphone pour ne pas être dérangé. (He turned off his phone so as not to be disturbed.)

Different subject: pour que / afin que + subjunctive
- Je t'écris pour que tu saches la vérité. (I am writing so that you know the truth.) — "saches" = subjunctive.
- Elle a expliqué lentement afin que tout le monde comprenne. (She explained slowly so that everyone would understand.) — "comprenne" = subjunctive.
- Nous sommes venus tôt pour que les enfants puissent jouer avant le dîner. (We came early so the children could play before dinner.)

Negative purpose
- Je ferme la porte pour que le chien ne sorte pas. (I close the door so that the dog won't get out.)
- Ils ont réduit le volume afin qu'on n'entende pas le bruit de la rue. (They lowered the volume so we wouldn't hear the street noise.)

De façon à / de manière à (infinitive) vs de façon à ce que / de manière à ce que (subjunctive)
- Il réorganise son agenda de façon à trouver du temps pour ses hobbies. (same subject: infinitive)
- Il a déplacé les chaises de façon à ce que tout le monde puisse voir. (different subject: subjunctive)

De sorte que (purpose vs result)
- Purpose (subjunctive): Il a fermé les fenêtres de sorte que la maison reste calme. (He closed the windows so that the house would stay quiet.) — use subjunctive to stress intention.
- Result (indicative): Il a fermé les fenêtres, de sorte que la maison est devenue plus calme. (He closed the windows, so the house became quieter.)

Quick reference / checklist

- Are the subjects the same? Yes -> use pour / afin de + infinitive.
- Are the subjects different? Yes -> use pour que / afin que + subjunctive.
- Is the sentence describing an intended goal (purpose)? Use subjunctive after que-connectors.
- Is the sentence stating an actual result? Use the indicative with result connectors.
- Use "afin de" in formal writing; "pour" is common in speech.

Glossary (simple definitions)

- Subjunctive (subjonctif): a verb mood used for wishes, doubts, intentions or actions not yet realized. After "pour que" / "afin que" you usually use the subjunctive.
- Infinitive: the base (unconjugated) form of the verb (e.g., parler, finir, être). Used after "pour" and "afin de" when the subject is the same.
- Indicative: the normal mood for stating facts and results.
- Main clause: the principal part of a sentence. It can be followed by a subordinate (dependent) clause that expresses purpose.
- Subordinate clause / purpose clause: a dependent clause introduced by "que" (e.g., "pour que..."), expressing the goal or intention.

Final tips

- The easiest way to choose quickly: check whether the actor of the purpose is the same as the actor of the main action. If yes, use "pour" / "afin de" + infinitive; if no, use "pour que" / "afin que" + subjunctive.
- Learn a few common subjunctive forms (être, avoir, aller, pouvoir, faire, savoir, vouloir) — they appear often after purpose conjunctions.
- Prefer "pour" in conversation and "afin de" in more formal or written contexts.

This guide gives you the main patterns and many examples. When in doubt, write the sentence and ask: who performs the purpose action? That single check will usually tell you whether to use an infinitive or a subjunctive clause.