The river becomes rapid as it passes __________ deep valleys, travelling __________ western Yunnan Province.
—Why does the lake smell terrible ? --because large quantities of water ____.
My parents have promised to come to see me before I ___for Africa.
The way the guests____in the hotel influenced their evaluation of the service.
Over the past decades , sea ice _____in the Arctic as a result of global warming.
--I would why he ____so strangely these days. --Recent pressure at study may account for his behavior.