这个问题千头万绪三言两语说不清楚: this problem is too complicated to be explained in a few words
大概: 1.(大致内容或情况) general idea; broad outline 短语和例子只知道个大概 have only a general idea2.(大约) general; rough; approximate 短语和例子大概的估计 a rough estimate; 大概的数字 an approximate figure; 大概的分析 a general ana