Learn Italian: Non lavorava ancora da infermiere. - He was not working as a nurse yet.

In Italian, when you want to say you are acting in a specific role or working in a profession, you use da without an article. You could use come (come infermiere), which is also correct and means "in the capacity of a nurse." However, using da is a very common, idiomatic way to express playing a role or working a job.

Why isn't there an article before infermiere? Shouldn't it be da un infermiere?

When da is used to indicate a role, profession, or stage of life (like da bambino), you drop the article completely. Saying da un infermiere would change the meaning to "at a nurse's place" or "by a nurse" instead of "as a nurse."

Why is ancora placed right after the verb instead of at the end of the sentence?

In Italian, adverbs of time like ancora (yet/still) and già (already) typically go immediately after the verb they modify. So, non lavorava ancora is the natural word order, unlike English where "yet" often goes at the very end of the sentence.

Why is the verb lavorava in the imperfect tense rather than the passato prossimo?