Incorrect spelling, explanation: for some regular verbs in English, it is not enough to add the -ed suffix to the root if we want to create a past simple form, a past participle form, or an adjective participle. Sometimes we need to do one more thing: double the last consonant in a word. Why? Because of an important rule: when there is a single vowel before the last (and stressed as well) consonant in a word, we have to double that consonant. Therefore, the only correct version is swapped, not swaped.

Correct spelling, explanation: the form swapped consists of two elements: a word-formation base and a suffix. Other than that, one detail should be noted: the -p letter was doubled. If you’re wondering why we have a simple explanation for you. There is an important principle in English: if the word has one vowel and it ends in one consonant, you double the last consonant before you add -ed. If you follow this rule, you’ll get the following version: swapped. Swaped isn’t right.

Definition of swapped:
verb (past simple, past participle), an act of exchanging one thing for another
Me and my new friend swapped phone numbers.
On Tuesday we swapped our video games.

Collocations with swapped:
Some most commonly used collocations include: swap ideas/stories, swap places
When we were on a trip, we swapped stories about our children.
My classmate forgot her glasses the other day, so I swapped places with her so she could see better.