Gari langu ni tofauti na gari lako.

They are possessive forms:

• langu = my
• lako = your (singular)

So:

• gari langu = my car
• gari lako = your car

In Swahili, possessives usually come after the noun, not before it as in English.

Because Swahili possessives must agree with the noun class of the noun they describe.

Gari belongs to the class 5 singular pattern, so the possessive uses la-:

• gari langu = my car
• gari lako = your car
• gari lake = his/her car

If the noun belonged to a different class, the possessive form would change. For example:

• kitabu changu = my book
• mtoto wangu = my child

So yangu is not the right agreement form for gari.

Ni is the verb to be in this kind of sentence. Here it means is.

So the structure is:

• Gari langu = my car
• ni = is
• tofauti na gari lako = different from your car

Swahili often uses ni in simple identification or description sentences.

tofauti na means different from.

It is best learned as a fixed expression:

• A ni tofauti na B = A is different from B

So:

• Gari langu ni tofauti na gari lako = My car is different from your car

Even though na often means and or with, in this expression tofauti na, it means from in English.

Because Swahili words often have more than one use depending on the expression.

Na commonly means:

• and
• with
• in some set phrases, something closer to from or a comparison link

In tofauti na, the full phrase means different from. So you should understand the whole expression together, not word by word.

Yes, you often can leave it out if the meaning is clear.

Both of these are natural:

• Gari langu ni tofauti na gari lako.
• Gari langu ni tofauti na lako.

The second version means literally My car is different from yours.
Here lako stands on its own, with gari understood.

Repeating gari is a little fuller and can be helpful for learners or when you want to be very clear.

Because Swahili generally does not use articles like English a, an, and the.

So gari can mean:

• a car
• the car
• just car

The exact meaning depends on context.

That is why Gari langu ni tofauti na gari lako does not need separate words for the or a.

Functionally, yes: it describes the car as different.

But it is helpful to know that Swahili does not always match English parts of speech neatly. In practice, you should learn:

• ni tofauti = is different
• tofauti na = different from

So even if you think of tofauti as acting like an adjective here, the most useful thing is to remember the pattern.

In gari lako, lako means your for one person.

If you are speaking to more than one person, you would use lenu:

• gari lenu = your car (plural)

So:

• Gari langu ni tofauti na gari lako. = My car is different from your car. (to one person)
• Gari langu ni tofauti na gari lenu. = My car is different from your car. (to more than one person)

The pattern is:

• noun + possessive
• ni
• description + na + comparison

So the sentence breaks down like this:

• Gari langu = my car
• ni = is
• tofauti na gari lako = different from your car

A very literal structure would be:

Car my is different from car your

That is normal Swahili word order for this kind of sentence.