Spelling rule
Adding prefixes
A prefix goes on the front of a word to change its meaning. The root word keeps its spelling, which is how some words end up with double letters.
How it works
- 1
Just add the prefix
- un + happy → unhappy
- dis + appear → disappear
- re + appear → reappear
- sub + marine → submarine
- super + market → supermarket
- 2
Same letter twice? Keep both
- dis + satisfied → dissatisfied
- un + necessary → unnecessary
- mis + spell → misspell
- im + mature → immature
- 3
in- becomes im-, il- or ir-
im- before m or p, il- before l, ir- before r.
- impossible
- immature
- illegal
- irregular
- inactive
- 4
Prefixes with meanings
- bi- (two): bicycle
- inter- (between): interrupt, interfere
- de- (down, away): describe, decrease
- re- (again): recommend, rebuild
Watch out
- disappear has one s and two p's (dis + appear); dissatisfied has two s's (dis + satisfied).
Words to practise
Years 3 and 4 statutory words
- disappear
- bicycle
- describe
- increase
Years 5 and 6 statutory words
- interrupt
- interfere
- recommend
- immediate
More everyday words
- unhappy
- misspell
- illegal
- irregular
- impossible
Practise a few minutes a day
The daily spelling workout brings back the words your child finds tricky, and shows you which rules they need to revisit.