It can flow directly into the river or go through tributaries first .
It can flow directly into the river or go through tributaries -LRB- smaller rivers that flow into the bigger river -RRB- first .
It can flow directly into the river or go through tributaries -LRB- smaller rivers that flow into the bigger river -RRB- first .
让这件事变得更简单: It can flow directly into the river or go through tributaries first . 输出: