Not knowing what version of iPad to choose, _____.
--Why does the lake smell terrible? ---Because large quantities of water ______.
—Miss Wang,I feel very nervous with the competition approaching. —________. As long as you can finish it,it is a victory.
Since our country has so many good table tennis players, we have to ______ the best ones to take part in the game.
— What has Jack been doing recently? —I don’t know _____ care.
Such a custom came into _______ long ago.