crowds or crowded Are these sentences ok? I wrote a sentence (There were huge crowded of people everywhere.) and my teacher correct it to me that below. There were huge crowds of people everywhere. There were crowded street everywhere. (Could you tell me what can I say with crowded if it isn't correct?) Sometimes I'm not using the right combination some words and I'm looking for some rules or explanation it.

my friend is visiting to me Hello Everybody! My friend is coming in April and this is her first time here. Even her brother was here for a half year in the Dublin University but only their parents visited him in that time. We are meeting in Dublin and sightseeing only 1 day and then we are going to Cork and I'll show her my life here. I'm planning we will go to the Cliffs of Moher, Cobh, Blarney and around in Cork county somewhere else. I want to show her many beautiful places in Ireland. I'm so looking forward to meet her in Dublin.

didn't know or haven't known Hi, I heard a news from someone she is lifelong sick as me. And I know about this makes problem and you have care about more. How can respond to her. I know her a bit but not everything. - Oh I didn't know that. Everything is ok with you? or - Oh I haven't known that. Everything is ok with you? or (I saw some where some good examples and maybe I can use these tenses are like as below) - Oh I didn't know that. Why haven't told me before? Everything is ok with you?