A la meva germana no li agrada el menjar picant, però a mi sí.

Because with agradar, Catalan usually marks the person who experiences the feeling with a.

So A la meva germana literally means to my sister.
Catalan structures this idea more like:

• To my sister, spicy food is not pleasing
• rather than English My sister doesn’t like spicy food

This is very normal with agradar.

Yes, they refer to the same person, and that is normal in Catalan.

• a la meva germana = to my sister
• li = to her

Catalan often uses this kind of doubling with indirect objects. The full noun phrase makes it clear who we are talking about, and the pronoun is still kept because it is part of the normal sentence structure.

So:

• A la meva germana no li agrada...

is more natural than leaving out li.

Because the verb agrees with the thing that is liked, not with the person who likes it.

Here, the subject is:

• el menjar picant = spicy food

That is grammatically singular, so the verb is singular:

• agrada

Compare:

• Li agrada el menjar picant. = He/She likes spicy food.
• Li agraden els menjars picants. = He/She likes spicy foods.

So the verb changes according to the thing causing the pleasure, not according to la meva germana.

Agradar works almost the opposite of English to like.

In English:

• My sister likes spicy food.

In Catalan, the logic is closer to:

• Spicy food pleases my sister.

So the structure is:

• person affected → introduced by a
• indirect object pronoun → li
• verb agradar
• thing liked

That is why the sentence looks different from a direct word-for-word English pattern.

Because no normally goes before the verb in Catalan, and unstressed pronouns like li go right before the verb too.

So the order is:

• no + li + agrada

This is the normal pattern:

• No m’agrada
• No li agrada
• No ens agrada

Putting no after the pronoun would sound wrong in standard Catalan.

Catalan often uses the definite article more than English does.

• el menjar picant = spicy food

Here el helps present it as a general category or type of food. This is very natural in Catalan.

You may also hear menjar picant in some contexts, but el menjar picant is perfectly normal and idiomatic here.

Picant means spicy or hot (in the sense of food with heat).

It comes after the noun because adjectives in Catalan often follow the noun:

• menjar picant = spicy food
• casa gran = big house

That post-noun position is much more common in Catalan than in English.

Because Catalan, like English, can leave out repeated material when it is obvious from context.

So:

• A la meva germana no li agrada el menjar picant, però a mi sí.

means:

• My sister doesn’t like spicy food, but I do.

The full version would be something like:

• ..., però a mi sí que m’agrada el menjar picant.

But Catalan often shortens this to a mi sí because the meaning is already clear.

Because this is the same structure as before: the person affected by agradar is expressed with a.

So:

• a mi = to me
• not jo = I

With agradar, you do not normally use jo as the person who likes something. Instead, you use the indirect-object pattern:

• A mi m’agrada
• A tu t’agrada
• A ell li agrada

So però a mi sí literally means but to me, yes.

Here sí means yes, but more specifically it is contrasting with the earlier no.

So the sentence sets up a contrast:

• my sister: no
• me: sí

That is why sí is enough on its own in the second half: it means yes, it does please me / yes, I do like it.

Also note the accent:

• sí = yes
• si = if

The accent matters.

Yes, but that would mean something slightly different.

• el menjar picant = spicy food
• menjar picant = can be understood as to eat spicy food

So:

• No li agrada el menjar picant = She doesn’t like spicy food.
• No li agrada menjar picant = She doesn’t like eating spicy food.

In many situations the meanings are close, but the grammar is different:

• one uses a noun phrase
• the other uses an infinitive phrase

Yes, extremely common.

This same structure appears with many everyday sentences:

• M’agrada el cafè. = I like coffee.
• No li agraden els gats. = She doesn’t like cats.
• A nosaltres ens agrada viatjar. = We like travelling.

So if you understand this sentence, you are learning one of the most useful basic Catalan patterns.