Mi prima empezó a tiritar en la parada porque salió sin jersey y hacía mucho viento.

After empezar, Spanish normally uses a + infinitive when you say someone begins to do something.

• empezó a tiritar = she started shivering

This is the usual pattern:

• Empezó a llover = It started to rain
• Empecé a estudiar = I started studying

So empezó tiritar would sound incomplete or ungrammatical in standard Spanish.

Tiritar means to shiver or to tremble from cold. It is quite specific here.

• tiritar = to shiver, especially because you are cold
• temblar = to shake or tremble more generally

So in this sentence, tiritar is a very natural choice because the cause is cold and wind.

Examples:

• Estoy tiritando de frío = I’m shivering with cold
• Temblaba de miedo = He/She was trembling with fear

This is one of the most common tense questions in Spanish.

• salió is preterite because it refers to a completed action: she went out / left
• hacía is imperfect because it describes the background situation: it was windy

So the sentence combines:

• a completed event: salió sin jersey
• an ongoing condition: hacía mucho viento

This is very typical in Spanish:

• Salió = one specific action
• Hacía mucho viento = the weather condition at the time

Spanish often uses hacer for weather expressions.

• Hace calor = It’s hot
• Hace frío = It’s cold
• Hace sol = It’s sunny
• Hace viento = It’s windy

So hacía mucho viento literally looks like it was making a lot of wind, but in natural English it means it was very windy.

This is just the normal Spanish structure for this kind of weather expression.

Because mucho modifies a noun, while muy modifies an adjective or adverb.

Here, viento is a noun:

• mucho viento = a lot of wind

Compare:

• hacía mucho viento = there was a lot of wind
• estaba muy ventoso = it was very windy

So:

• mucho + noun
• muy + adjective/adverb

In Spain, jersey commonly means jumper, sweater, or pullover.

That is an important regional vocabulary point:

• In Spain: jersey = sweater/jumper
• In some other varieties of Spanish, people might say suéter, pulóver, or something else

So this sentence is very natural for Peninsular Spanish.

After sin, Spanish often leaves out the article when speaking generally.

• salió sin jersey = she went out without a sweater

This sounds natural and idiomatic. Adding un is possible in some contexts, but here it is not necessary and usually less natural.

Compare:

• Salió sin abrigo = He/She went out without a coat
• Estoy sin móvil = I’m without my phone / I don’t have my phone on me

So sin + noun often works without an article.

La parada means the stop, and in this context it usually means the bus stop or the stop where she was waiting.

In everyday Spanish, if the context is clear, la parada often refers to a public transport stop.

Examples:

• la parada de autobús = the bus stop
• la parada del tranvía = the tram stop

So en la parada means at the stop.

Porque means because and introduces the reason.

Here:

• Mi prima empezó a tiritar en la parada porque salió sin jersey y hacía mucho viento.
• She started shivering at the stop because she went out without a sweater and it was very windy.

A useful distinction:

• porque = because
• por qué = why

Examples:

• No vino porque estaba enfermo = He didn’t come because he was ill
• ¿Por qué no vino? = Why didn’t he come?

Spanish often omits subject pronouns because the verb ending already shows the person.

• empezó
• salió

Both are third person singular, and the subject is already clear from mi prima.

So Spanish does not need ella here. In fact, adding ella would usually sound unnecessary unless you want emphasis or contrast.

Natural:

• Mi prima empezó...

Less necessary unless emphasizing:

• Mi prima, ella empezó...

Mi prima means my female cousin.

Spanish distinguishes:

• primo = male cousin
• prima = female cousin

English uses just cousin, but Spanish marks gender in the noun.

So:

• mi primo = my male cousin
• mi prima = my female cousin

The accent mark shows the correct stress.

• empezó is the third person singular preterite form of empezar
• The stress falls on the last syllable: em-pe-ZÓ

Without the accent, empezo would be spelled incorrectly.

This is part of a broader pattern in many preterite forms:

• habló
• comió
• salió
• empezó

Yes. Comenzó a tiritar is also correct and means the same thing.

• empezar = to begin, to start
• comenzar = to begin, to start

Both are common, though empezar often feels a bit more everyday and frequent in casual speech.

So these are both fine:

• Mi prima empezó a tiritar
• Mi prima comenzó a tiritar

Yes, Spanish is flexible with word order.

The original order is very natural:

• Mi prima empezó a tiritar en la parada porque salió sin jersey y hacía mucho viento.

But you could also rearrange it:

• Como salió sin jersey y hacía mucho viento, mi prima empezó a tiritar en la parada.

That version puts the cause first. Both are grammatical, but the original is a very normal way to say it in everyday Spanish.

Yes. Salir can mean both, depending on context.

In this sentence, salió sin jersey means something like:

• she went out without a sweater
• she left the house without a sweater

English may choose different wording, but the Spanish verb salir covers that idea naturally.

Examples:

• Salí de casa temprano = I left home early
• No salgas sin chaqueta = Don’t go out without a jacket