ENGLISH 101: WHEN TO DOUBLE CONSONANT

Is it dialled or dialed?

When adding -ing and -ed to verbs, we sometimes double the consonant beforehand. People are often confused with ‘dialled/dialed’, ‘benefitted/benefited’, ‘focussed/focused’ and ‘targetted/targeted’. This tip answers some of those queries.

The official requirements are that we ‘double a single consonant letter at the end of any base where the preceding vowel is spelled with a single letter and stressed’.

What does this mean in practice?

Examples:

word	present participle	past participle
bar	barring	barred
beg	begging	begged
occur	occurring	occurred
permit	permitting	permitted
patrol	patrolling	patrolled

It is true to say that there is usually no doubling when the preceding vowel is unstressed (‘enter’ becomes ‘entering/entered’; ‘visit’ becomes ‘visiting/visited’) or when the preceding vowel is written with two letters (‘tread’ becomes ‘treading/treaded’).

Dial

With ‘dial’, even though the preceding vowel is written with two letters (so you would think that there would be no doubling), it becomes ‘dialling/dialled’ (though not in American English, as mentioned).

Some words change their spelling to cope (they add a letter ‘k’).

word	present participle	past participle
panic	panicking	panicked
traffic	trafficking	trafficked
frolic	frolicking	frolicked
bivouac	bivouacking	bivouacked

What about ‘focus’?

This word can take either double or single s, with the single option being highly preferred.

word	present participle	past participle
focus	focusing/focussing	focused/focussed

Here’s an odd one to end:

American	British English
parallel	parallel
paralleling	parallelling
paralleled	parallelled

Example:

The vetting service from Future Perfect is unparallelled.