What is a past participle?
Most verbs have three forms: the base form (V1), the past simple (V2) and the past participle (V3).
- Regular verbs add -ed to V1 for both V2 and V3: walk, walked, walked; power, powered, powered.
- Irregular verbs change shape: grow, grew, grown; drive, drove, driven; build, built, built; make, made, made; write, wrote, written.
Tip: learn irregular verbs in small groups, such as build/built/built, send/sent/sent, bring/brought/brought.
Three jobs of the past participle
- Passive voice: be + participle. The data is stored in the cloud. Cities will be powered by clean energy.
- Perfect tenses: have/has/had + participle. Scientists have built a robot that can walk.
- Describing a noun (like an adjective): a broken window, a robot built in a lab, food grown in towers.
Participle phrases after a noun
A participle phrase after a noun is a short way to say a longer clause. Food that is grown in towers becomes food grown in towers. A car which is driven by AI becomes a car driven by AI. We drop 'that is' or 'which is' and keep the participle plus the rest.
Rule: the noun receives the action. Food is grown (by someone), a car is driven (by something). The action is done to the noun, so we use the past participle, not the -ing form.
Talking about future technology
Many experts think that in the coming decades more energy will come from the sun and wind, more cars will have driver-assist or self-driving features, more food will be grown close to cities, and helper robots will be used in hospitals and homes. Nobody knows exactly what will happen, so use careful words: may, might, will probably, is likely to.
Useful sentence patterns:
- In the future, more homes will be powered by solar panels.
- Robots built for care work may help older people.
- Food grown near cities will travel shorter distances.
Try it: label your home of the future
Do this in 10 minutes. Draw your house or classroom in 2050. Add four inventions. Label each with a participle phrase: a window cleaned by drones, a lamp powered by the sun, books stored in a tiny chip, a garden watered by sensors. Then write one sentence for each with 'will be': Our garden will be watered by sensors. Check each participle in the 3D buttons list or in a dictionary.
Key formulas and definitions
- V1 (base) โ V2 (past) โ V3 (past participle): grow โ grew โ grown
- Regular: V1 + -ed (power โ powered โ powered)
- Passive: be + V3 (will be powered)
- Perfect: have/has/had + V3 (has built)
- Noun + V3 + rest = reduced clause (food grown in towers)
Worked examples
1. Write the past participle of: grow, drive, build, power, write.
grown, driven, built, powered, written.
2. Shorten 'The robot which was built in India helps patients.'
The robot built in India helps patients.
3. Make a future passive sentence: 'The sun powers the house.'
The house will be powered by the sun.
4. Fill in with the participle of 'make': 'Chairs ___ from recycled plastic are strong.'
made. 'Chairs made from recycled plastic are strong.'
5. Which is correct: 'a car driving by AI' or 'a car driven by AI'?
'driven by AI'. The car receives the action of driving, so we use the past participle.
6. Write a present perfect sentence about technology using 'build'.
Engineers have built tall farms in cities. (have + built)
Common mistakes
- Using the past simple instead of the participle: 'I have grew' is wrong; 'I have grown'.
- Using -ing when the noun receives the action: 'a robot building in a lab' means the robot builds; use 'built' if the robot was built.
- Forgetting 'be' in the passive: 'The house will powered' is wrong; 'will be powered'.
- Adding -ed to irregular verbs: 'drived' and 'growed' do not exist.