Sometimes there is a spelling change when the -s, -ing, and -ed endings are added.
In the following verbs ending in e, you just add -ing in the normal way to form the -ing form. For example, the -ing form of age is ageing.
You don't double the final consonant of verbs ending in w, x, or y when forming the -ing form or past form.
- row -- rowing -- rowed
- box -- boxing -- boxed
- play -- playing -- played
In British English, you double the final l of verbs like travel and quarrel, even though the last syllable is not stressed.
- travel -- travelling -- travelled
- quarrel -- quarrelling -- quarrelled
You don't double the final l in American English. In British English, and sometimes in American English, the final consonant of the following verbs is doubled, even though the last syllable is not stressed.
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