is this really like very or in truth
It is used as both (just like English), but literally it would be like "in truth."
it may mean both but literally it is more like in truth.
Gerçek means real, so gerçekten is like from reality, or in truth, or just really
"This house is really huge"
yazdım kabul etmedi
can you simply use "gerçekten zor" as a reply in the following situation:
Some friend: "Bu kitap zor". Me, agreeing and reaffirming the situation: "Gerçekten zor!"