Learn Spanish (Latin America): La abuela tiene muy buen oído.

Spanish has two words for "ear." Oreja refers to the physical, outer part of the ear that you can see (the part you might pierce). Oído refers to the inner ear and the actual sense of hearing. Since Grandma has a good sense of hearing, we use oído.

Why does it say buen instead of bueno?

When the adjective bueno comes directly before a masculine singular noun (like oído), it drops the final "o" and becomes buen. If it came after the noun, it would be un oído muy bueno, but putting it before the noun is the most natural word order for this expression.

Is oído related to the verb oír from this lesson?

Yes! Oír is the verb meaning "to hear," and oído is the noun for the sense of hearing. Oído also happens to be the past participle of oír (meaning "heard"), but in this sentence, it is functioning as a noun.

Why is there a "La" before "abuela" if the English translation is just "Grandma"?

In English, we often use family words like "Grandma" or "Mom" almost like proper names, without using "the." In Spanish, when you are talking about a specific family member rather than talking directly to them, it is much more common to include the definite article (el or la).