Answer:
It has the biggest wall and is also used when drinking tea.
What comes one time in today, three times in tomorrow and never in the future?
What can't you see, hear or feel, until it’s too late. What shadows love, and shopkeepers hate?
The buyer doesn’t want it, the producer doesn’t need it and the user doesn’t know their using it.
What occurs four times in every week, twice in every month, only once in a year but never in a day?
I touch the Earth, I touch the sky, but if I touch you, you’ll likely die. What am I?