Learn Portuguese (Portugal): Não preciso do teu bilhete.

In Portuguese, you often drop the pronoun eu (I) because the verb ending already tells us who is doing the action. Preciso always means "I need", so adding eu is not strictly necessary.

Why does the sentence use do instead of just de after the verb?

The verb precisar (to need) requires the preposition de. However, in European Portuguese, we almost always put a "the" (definite article) before possessive words like teu. When de meets o (the masculine "the"), they combine to form the contraction do.

Wait, why is there a "the" before "your"? In English we just say "your ticket".

That is a common pattern in European Portuguese! Before possessive words like teu (your), you usually include the definite article. Since bilhete is a masculine word, we use o, giving us o teu bilhete (literally "the your ticket"). Combined with the de from precisar, it becomes do teu bilhete.

Why is it teu and not tua?