Don’t raise a flag telling your readers that you don’t know when to spell words like signaling (Or is it signalling?).
The doubling of the l when adding a suffix to a word tends to be a British convention. So, if you are in America, use signaled. If you’re in Britain, use signalled.
Other words this rule applies to includes:
AMERICAN: fueling, marveling, modeling, traveling
BRITISH: fuelling, marvelling, modelling, travelling
An exception in America is when the stress of the word falls on the second syllable. Then use a double l, as in: annulled, expelled, extolled, patrolled.
A few British spellings also stick with a single l, though they are few: appealed, devilish, loyalist, travelogue.
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My name is Rob Bignell. I’m an affordable, professional editor who runs Inventing Reality Editing Service, which meets the manuscript needs of writers both new and published. I also offer a variety of self-publishing services. During the past decade, I’ve helped more than 300 novelists and nonfiction authors obtain their publishing dreams at reasonable prices. I’m also the author of the 7 Minutes a Day… writing guidebooks, four nonfiction hiking guidebook series, and the literary novel Windmill. Several of my short stories in the literary and science fiction genres also have been published.