Learn Portuguese (Portugal): Boa sorte no trabalho!

The word for luck, sorte, is a feminine noun in Portuguese. Adjectives must match the gender of the noun they describe, so we use the feminine word for good (boa) instead of the masculine (bom).

How does no mean 'at' in this sentence?

In English, we say 'at work', but in Portuguese, the phrase literally translates to 'in the work'. The word no is a mandatory combination of the preposition em (in/at) and the masculine word for 'the', o. Since trabalho is a masculine noun, they merge into no.

I learned that trabalho means 'I work'. Is it a verb here?

Great catch! While trabalho is the 'I' form of the verb trabalhar (to work), it is also the noun for 'work' or 'job'. The clue here is the word no right before it. Because it translates to 'in the', we know the next word must be a noun.