Doubling Consonants
A2 · ElementarySpelling RulesStop → stopping, big → bigger, prefer → preferred — doubling the final consonant keeps the vowel sound short.
What you'll learn
- A short word ending in a single vowel letter + a single final consonant usually doubles that consonant before -ed, -ing, -er, or -est: stop → stopping, big → bigger
- This doubling exists to keep the vowel's short sound — without it, the word would look like it has a long vowel sound instead
- For longer words, the same rule applies only if the stress falls on the last syllable: prefer → preferred, but open → opened (stress on the first syllable, no doubling)
- British English doubles a final -l even when the stress isn't on the last syllable: travel → travelled (British) vs. traveled (American, covered further in British vs American Spelling)
The 1-vowel, 1-consonant rule
When a short word ends in a single vowel letter followed by a single consonant, that final consonant usually doubles before an ending starting with a vowel (-ed, -ing, -er, -est). This keeps the vowel sounding short, the way it does in the base word.
Why doubling protects pronunciation
Compare a word that doubles with one that doesn't: 'hop' and 'hope' look almost identical, but their -ing forms show the difference clearly. Doubling the consonant signals a short vowel; leaving it single (after a silent -e is dropped) signals a long vowel.
Longer words: it depends on stress
For words with more than one syllable, doubling only happens if the stress falls on the final syllable. If the stress is earlier in the word, there's no doubling.
Real English
Watch out
'shop' needs its final consonant doubled before -ing (shopping) — without it, 'shoping' looks like it comes from a word spelled 'shope'.
'visit' is stressed on the first syllable, so its final -t does NOT double before -ed — doubling only applies when the stress falls on the last syllable.
Real life — Planning a trip
"Have you decided where you're traveling this summer?"
"We're still planning, but we're preferring somewhere warm."
"That sounds nice! Are you stopping anywhere on the way?"
"Maybe — we haven't committed to anything yet."
Practice
Exercise 1 · Choose the correct spelling
Choose the correct -ing form: stop → ___
Exercise 2 · Choose the correct spelling
Choose the correct -ed form: plan → ___
Exercise 3 · Choose the correct spelling
Choose the correct -er form: big → ___
Exercise 4 · Choose the correct spelling
Choose the correct -ing form: open → ___ (stress is on the first syllable)
Exercise 5 · Choose the correct spelling
Choose the correct -ed form: prefer → ___ (stress is on the last syllable)
Exercise 6 · Choose the correct spelling
Choose the correct -ed form: visit → ___ (stress is on the first syllable)
Exercise 7 · Choose the correct answer
Why does 'stop' become 'stopping' but 'cook' becomes 'cooking' (no doubling)?
Exercise 8 · Choose the correct spelling
Choose the correct -ing form: travel → ___ (British spelling)
Exercise 9 · Add the correct ending
Add -ing correctly: swim → ___
Exercise 10 · Add the correct ending
Add -est correctly: hot → ___
Exercise 11 · Sort the words into groups
0 / 8 sorted
Quick challenge
Five quick questions to check what stuck.
Question 1 / 5
Score: 0/0
Choose the correct -ing form: begin → ___ (stress on the last syllable)
You learned
- A word ending in a single vowel + single consonant usually doubles that consonant before -ed/-ing/-er/-est: stop → stopping.
- Doubling keeps the vowel sounding short, as in the base word.
- For longer words, doubling only happens if the stress falls on the last syllable: prefer → preferred, but open → opened.
Related grammar lessons
Words Ending in -e
Learn when to drop a word's silent final -e before adding a suffix, and when to keep it — drop before a vowel suffix like -ing, keep before a consonant suffix like -ly — plus the small set of exceptions that keep the -e to avoid confusion or preserve pronunciation.
Words Ending in -y and -ie
Learn when a final y changes to i before a suffix (and when it doesn't), plus the special rule for words ending in -ie before -ing — study → studied, but studying; play → played; die → dying.
Adding -s, -ed and -ing
An overview of why English spelling shifts when you add -s, -ed, or -ing to a word — the general idea that spelling changes exist to protect pronunciation — with the specific rules (doubling, dropping -e, changing y to i) each getting their own dedicated lesson.
British vs American Spelling
Learn the systematic spelling differences between British and American English — -our/-or, -re/-er, -ise/-ize, -ogue/-og, and doubling before a suffix — and why picking one system and staying consistent matters more than which one you choose.