Learn Italian: Mangio gli spaghetti con il pomodoro.

In Italian, subject pronouns like io (I) are usually dropped because the verb ending already tells you who is doing the action. The -o ending on mangio lets us know it specifically means "I eat".

Why is the article gli used for spaghetti instead of i?

Even though i is the most common masculine plural word for "the", Italian uses gli before masculine words that start with an s followed by a consonant. Since spaghetti starts with sp-, it has to be gli spaghetti.

Don't small connecting words like con usually combine with the word for "the"?

Often, yes! Many prepositions merge with definite articles to form a single word (for example, a + il becomes al). However, con (with) is an exception. It is standard in modern Italian to keep con and il separate, though you might occasionally see the combined form col.

Why does Italian use il pomodoro ("the tomato") when English just says "with tomato"?

Italian uses definite articles (like il, la, gli) much more often than English does. When talking about a sauce or the main flavoring ingredient of a dish, Italian typically includes the article, so "with tomato sauce" or "with tomato" becomes con il pomodoro.