Causative structures express the idea that someone arranges for another person to do something for them, rather than doing it themselves. 'Have something done' and 'Get something done' are the most common causative forms in English.
Quick tip: have/get + object + PAST PARTICIPLE = arrange a service. have/get + person + TO-INFINITIVE = persuade someone to do something.
Have + Object + Past Participle (Passive Causative)
Use 'have + object + past participle' to say someone arranges for a service to be done by someone else (usually a professional). Focus is on the service, not who does it. More formal than 'get'.
I had my hair cut yesterday. (Someone cut my hair for me - I arranged it)
She's having her house painted next week. (Painters will paint it for her)
We need to have the car repaired. (A mechanic will repair it)
They had their windows cleaned. (A window cleaner cleaned them)
Get + Object + Past Participle (Passive Causative)
Use 'get + object + past participle' with the same meaning as 'have' - arranging for someone to do something. 'Get' is more informal and suggests more effort or difficulty in arranging the service.
I need to get my phone fixed. (Informal, suggests it's urgent or difficult)
We're getting the bathroom renovated. (Arranging for builders to do it)
She finally got her visa approved. (It took effort or time)
They got their taxes done by an accountant. (Arranged for professional help)
Use 'have/get + person + to do' to say you persuade, ask, or arrange for a specific person to do something. This focuses on who does the action. 'Get' suggests more persuasion needed.
I had my brother help me move. (I arranged for him to help)
She got her friend to lend her the money. (She persuaded her friend)
We couldn't get him to change his mind. (We tried to persuade him but failed)
They had the neighbors look after their cat. (They arranged it with the neighbors)
Common mistakes
Not "I had cut my hair yesterday." — say "I had my hair cut yesterday.". Causative: have + object + past participle (someone else cut it). 'I cut my hair' means I did it myself..
Not "She got her house painting next week." — say "She's getting her house painted next week.". Causative needs past participle (painted), not present participle (painting). Pattern: get + object + past participle..
Not "We need to have the mechanic to repair the car." — say "We need to have the car repaired. OR We need to get the mechanic to repair the car.". Two patterns: 'have + object + past participle' (no 'to') OR 'have/get + person + to-infinitive'. Don't mix them..
Practise it
Ask yourself: Did I do it myself (regular verb) or did someone else do it for me (causative: have/get + done)?