The /ɑːr/ of car and farm. Reliable in a stressed syllable — and reliably something else after w, and in an unstressed one.
R-controlled vowels
ar R_AR_01
Strong rule · High reliability · Very common · Early · Reading and spelling
/ɑːr/ ar: car, farm, star
/ɔːr/ ar after w: warm, war, ward
/ər/ unstressed ar: dollar, sugar, collar
Where Wiggler teaches it: Skill 8: R-Controlled Vowels
Child explanation
A and r together say /ɑː/ — the sound in car and star. But after a w, it changes: warm, not warrm.
The rule
Ar represents /ɑːr/ in a stressed syllable. After w it is /ɔːr/ instead, and in an unstressed syllable it reduces to /ər/.
What is really going on
Reliable in stressed position. The w-conditioned retraction is the same process that turns want into /wɒnt/ — the lip rounding of /w/ pulls the vowel back. The unstressed reduction to /ər/ is part of the general schwa system and affects every r-controlled spelling equally.
war, warm, ward, dwarf, quarter, dollar, sugar, collar
Pseudo-words
Made-up words that follow the rule. A child who reads these has the pattern rather than the vocabulary.
blar, sharm, frard
Exceptions
ar after w: war, warm, ward, wart, dwarf, quarter, swarm. The /w/ rounds and retracts the vowel.
Unstressed -ar: dollar, sugar, collar, grammar, burglar. Schwa plus r, indistinguishable from -er or -or.
Contrast pairs
cat versus cart — Closed syllable versus r-controlled.
car versus war — The w changes everything.
star versus sugar — Stressed versus unstressed ar.
Decodable sentences
The car is parked in the dark yard.
A star is far from the farm.
It is hard to start a sharp cart.
Common reading mistakes
car: a child reads /kæ/ /r/, where the word is /kɑːr/. Vowel and r decoded separately.
warm: a child reads /wɑːrm/, where the word is /wɔːrm/. The w rule not applied.
Teacher note
Teach children to look for the r before deciding the vowel — the same scan-to-the-end habit that magic e needs. Introduce ar first of the five because it is the most reliable and the most distinctive by ear. Hold the w-changes-ar group back until ar is secure, then teach war, warm and ward as a family.
Accent notes
General American and Indian English — Rhotic: the r is pronounced in car and farm.
Southern British English — Non-rhotic: the r is not pronounced unless a vowel follows, so car is /kɑː/. The grapheme is still read as one unit, which is what matters for decoding.