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"Los guisantes" is a form of "guisante", a noun which is often translated as "pea". "La cebolla" is a form of "cebolla", a noun which is often translated as "onion". Learn more about the difference between "los guisantes" and "la cebolla" below.
el guisante()
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
a. pea
El chef preparó una ensalada de gambas con patatas y guisantes.The chef prepared a shrimp salad with potatoes and peas.
la cebolla()
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
1. (vegetable)