Elijo el auto compacto con transmisión manual.

Elijo is the first-person singular present indicative form of elegir.

So it is the yo form:

• yo elijo
• tú eliges
• él/ella elige
• nosotros elegimos
• ellos eligen

Two things happen in elijo:

• the stem vowel changes from e to i
• the g changes to j in the yo form

That is why it is elijo, not elego.

Spanish often drops subject pronouns because the verb ending already shows who the subject is.

• Elijo already means I choose / I am choosing
• so yo is not necessary

You could say Yo elijo el auto compacto..., but that usually adds:

• emphasis
• contrast
• clarification

For example:

• Yo elijo el auto compacto, no el SUV.

Without emphasis, leaving out yo sounds very natural.

Using el suggests a specific car is being chosen, not just any one.

• el auto compacto = a particular compact car, or the compact car in the situation
• un auto compacto = any compact car / one compact car

So the article changes how specific the noun feels.

Compare:

• Elijo el auto compacto = I choose the compact car
• Elijo un auto compacto = I choose a compact car

In Spanish, most descriptive adjectives normally come after the noun.

So:

• auto compacto not usually
• compacto auto

This is the standard word order for a normal, factual description.

Also, compacto agrees with auto, which is masculine singular:

• el auto compacto
• la camioneta compacta

Auto is widely understood across Latin America, but the most common everyday word depends on the country.

Some common regional preferences:

• auto: widely understood, fairly neutral
• carro: very common in many Latin American countries
• coche: very common in Spain, and also used in some Latin American countries, such as Mexico

So auto is a good general word for learners, especially in a broad Latin American context.

Here, con means the car has or comes with that feature.

So con transmisión manual describes the car as being equipped with a manual transmission.

This use is very common in Spanish when talking about product features:

• con aire acondicionado
• con motor híbrido
• con pantalla táctil

You could think of it as:

• a compact car with manual transmission

In Spanish, after con, the article is often omitted when you are talking about a feature or category in a general way.

So:

• con transmisión manual sounds natural
• con la transmisión manual would usually suggest a specific transmission, not just the general feature

Compare:

• un auto con transmisión manual = a car with manual transmission
• el auto con la transmisión manual nueva = the car with the new manual transmission

In your sentence, it is describing a type/specification, so no article is needed.

Because manual is an adjective that usually has the same form for masculine and feminine singular nouns.

So:

• el auto manual
• la transmisión manual

It does not change to match gender in the singular.

Only the plural changes:

• autos manuales
• transmisiones manuales

So manual works correctly with transmisión, even though transmisión is feminine.

A simple Latin American-style approximation is:

• elijo → eh-LEE-ho
• transmisión → trahns-mee-SYON

A few pronunciation notes:

• the j in elijo is like a strong English h, though often a bit rougher
• the stress in elijo is on LI
• the stress in transmisión is on the last syllable: -sión

So:

• e-LI-jo
• trans-mi-SIÓN

The accent mark shows that the stress falls on the last syllable:

• trans-mi-SIÓN

Without the accent, Spanish spelling rules would make you expect a different stress pattern.

This written accent is very common in nouns ending in -ión:

• nación
• estación
• transmisión

So the accent helps you pronounce the word correctly.

Yes. In Spanish, the simple present can often express:

• I choose
• I am choosing

The exact meaning depends on context.

So Elijo el auto compacto con transmisión manual could mean:

• a general decision
• a choice happening right now

If someone wants to be extra explicit about the action happening right now, they could also say:

• Estoy eligiendo el auto compacto con transmisión manual

But the simple present is very normal here.

Yes. Escoger and elegir can both mean to choose.

So you could say:

• Escojo el auto compacto con transmisión manual
• Elijo el auto compacto con transmisión manual

Both are correct.

In many contexts, elegir feels a little more neutral or standard, and it is extremely common. But escoger is also perfectly normal in everyday Spanish.

Yes, in many contexts you can, especially in product descriptions or technical language.

Compare:

• auto con transmisión manual = very natural, everyday way to say it
• auto de transmisión manual = also possible, sometimes a bit more descriptive or specification-like

For a learner, con transmisión manual is an excellent and very natural choice.