分析形势，要看清主流和支流。

In analysing a situation, it's essential to distinguish the main aspect from the minor ones.

《新英汉大辞典》

然而，古典芭蕾已经表明它是主流正如民间舞和交际舞一样，现代的剧场舞蹈是古典芭蕾舞的支流。

But classical ballet has shown that it is the mainstream; modern theatrical dance like folk and social dance is its tributary.

youdao