"하고" and "랑" are almost the same in terms of grammar, but "랑" is more informal meaning "with" or "and". Here are the usages of it. 1) noun + 랑/하고 = with 친구하고 영화관에 갔어요. = 친구랑 영화관에 갔어요. = I went to the movie with a friend of mine. 2) noun + 하고/랑+ noun = and (usually link two nouns) 너+하고+나는 공통점이 많아 = 너+랑+나는 공통점이 많아 = You and I have a lot in common. 3) Verb + (하)고 = and (then) 우리는 저녁먹고 영화보러 갔다. = We had dinner and went to the movie. "그리고(= and then)" can be used to link sentences or nouns. For example, 1) sentence + 그리고 + sentence a) 나는 저녁을 먹었다 = I had dinner b) 나는 영화관에 갔다 = I went to the movie Assuming a) happened and then b) happened, 나는 저녁을 먹었다 그리고 나는 영화관에 갔다. (I had dinner and (then) went to the movie) = 나는 저녁을 먹고 그리고 영화관에 갔다. = 나는 저녁을 먹고 나서 영화관에 갔다. (After I had dinner, I went to the movie) 2) noun + 그리고 + noun (link more than two) You and I = 너 그리고 나 (in written) = 너 하고 나(in spoken) = 너 랑 나(in spoken, more casual than "하고") I love to eat Ramyon, Naengmyeon, Bulgogi and Sundae. 저는 라면, 냉면, 불고기 그리고 순대를 좋아해요. \^O^/

가다 갔다(just a statement), 갔어요(in spoken, informal) ^^