Learn Polish: Nikt nigdy nie zszedł z tej drabiny. - Nobody has ever gone down this ladder.

Polish requires multiple negation. If you use negative words like nikt (nobody) or nigdy (never), you must still put nie in front of the verb. A literal translation would be 'Nobody never did not go down', but in English we just say 'Nobody has ever gone down'.

How does the prefix in zszedł change the meaning of the verb?

The base verb here is the past tense of iść (to go/walk on foot). Adding the prefix z- (or ze-) adds the direction of moving downward or getting off a surface. This prefix also makes the verb perfective, meaning the action of descending is viewed as fully completed.

I often see the 'he went down' form of zejść written as zeszedł. Why is it zszedł here?

The strictly correct, official dictionary form is indeed zeszedł, where an extra 'e' is added to make pronunciation easier. However, native speakers very frequently drop that 'e' and say or write zszedł in everyday Polish. You will encounter both, but it is safer to use zeszedł in formal tests.

Why did the phrase ta drabina (this ladder) change to tej drabiny?