Verbos con cambio ortográfico c > qu (pretérito Indefinido)

Stem-changing Spanish c>qu verbs in the simple past tense

Spanish verbs ending in -car undergo a change when they are conjugated in the simple past.
The -c- changes to -qu- but it only affects the yo form.
For example: 

buscar (to look for) → yo busqué

aparcar (to park) → yo aparqué

To see a list of verbs affected by this irregularity go to Verb list: -car verbs that change c > qu in the yo form in El Pretérito Indefinido.
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