used to form adjectives and nouns that say what country or area a person, thing, or language comes from

Spanish dancing 西班牙舞蹈

Are you English? 你是英格兰人吗？

I've always liked the Irish (= people from Ireland). 我一直喜欢爱尔兰人。

Do you speak Swedish? 你说瑞典语吗？

used to form adjectives that say what a person, thing, or action is like

foolish 傻子似的

childish 孩子气的

used to form adjectives to give the meaning to some degree; fairly

He had a sort of reddish beard. 他的胡子略带红色。

She was oldish - about 60, I'd say. 我想，她有点儿上年纪了——大约60岁。