It was about a newly wealthy black family that moved into a New York City high-rise with mostly white neighbors.
high-rise 是 adj/n, 意思是“高层建筑(的)”;mostly 意思是“主要地,多半”。 原句译文:它讲的是关于一个刚富裕起来的黑人家庭的事,这家人搬到了一幢纽约市的大厦,那儿多数邻居都是白人。