Teacher Discussion Forums

(Example) Since New Zealand's Edmund Hillary and Sherpa Tenzing Norgay first reached the top of Mt. Everest on May 29, 1953, about 1,200 other mountain climbers have reached THE PEAK.


I am wandering whether "the peak" is the object or adverbial.

It looks like the object in form.
However, it is translated as an adverbial in my mother tongue(Korean) , because it's a place.

What do you think of it in English view?

Grammar rules of one language cannot always apply to another language.
In your case, the verb REACH requires an OBJECT because it is a so-called TRANSITIVE verb. You cannot say "They reached!" Reached WHAT or WHOM? The answer: The Peak (object).
Adverbials on the other hand are OPTIONAL, and you find them after INTRANSITIVE verbs such as GO:
"They went" would be slightly substandard, although the verb GO is an intransitive verb. Use it in the imperative form "Go!" and contrast this with "Reach..." - clearly, "reach' must be followed by something, for instance "for it".
But we would feel that a verb "went" without anything following it sounds awkward. The place after it should be filled by an adverbial: "They went home' (adverbial of place). "They went at six o'clock" (adverbial of time).