car
The Italian word for car is 'auto'. It's used much like it is in English, to refer to an automobile or vehicle. For example: 'La mia auto è blu' means 'My car is blue'.
I have to wash my car
In this sentence, 'auto' is used as a noun to indicate a car. The phrase is a statement about a personal responsibility or task.
The car is fast
This sentence uses 'auto' as a noun. The phrase is providing a description of the car's speed.
I want to buy a new car
Here, 'auto' is used as a noun to indicate a car. The sentence is expressing a desire to purchase a new car.