Nearly: Was lädt er? with lowercase er is a valid German sentence.
It's not acceptable as an answer to a "type what you hear" exercise for Er lädt was?, of course.
I recall in some other thread you mentioned that German is more strict about asking questions that you can say something like "do what" in English, but not in German. Why is it valid here?
"Does he load something?" could be Lädt er was?
Was lädt er? would mean "What does he load? What is he loading?"
I translated this sentence as: "he is charging what?" and was considered wrong. I don't understand why because in the "dict.cc Wörterbuch" it says that "to charge" is another meaning of "laden". My translation would refer to charge a cell phone for example or to charge a battery. If any of my student colleagues cares to answer this question, I would appreciate it very much. I don't expect Duo to answer my question because they wrote this course and disappeared.
The verb laden can refer to (un)load or (re)charge. Some examples:
- Die Akkus müssen wieder geladen werden. The batteries need recharging.
- Bitte lade meine Autobatterie auf. Please charge my car battery.
- Ich muss das Gepäck aus dem Flugzeug laden. I have to unload the baggage from the plane.
- Glücklicherweise war der Revolver nicht geladen. Luckily the revolver wasn’t loaded.