question about all gw games

hi im new to guild wars and i just wanted to know that if i complete the missions on one of the games can i still keep playing it like killing monsters and making gold

Yes. You can repeat everything if you choose.

is they parts like on runescape were it says you need certain expantions to do certain things like go on certain areas

And, once you've completed the storyline, you can do them all over in Hard mode! Or you could try your hand at the Elite missions/areas that each game has to offer.

Well there is areas where you need to be a certain level before you can enter.

if i do it on hard mode do i do it on the same account as i did on normal

I think he means Expansions*..

And Yes, You need to have certain expansions in order to go to other continents. But you can still play the game fully with only one chapter.

Yep.. It's on the same character as well..

thank you i no i everything i need to no now

Thank you! I had been wondering this too, glad someone else asked

Once you complete a chapter/campaign (Prophecies, Factions, Nightfall) with one character, all your characters can play that chapter in Hard Mode whether they have completed it or not.

...so long as that character is Level 20. Hard Mode is only available to Level 20 Characters.