had taken such effective ______much earlier, the river would not bepolluted soseriously now.

Nowadays, more and more people would rather ____ __ in the country, because there is __ ____pollution there than in the city.

Money is very important, ________ it is notthe most important thing.

was the trouble with you the day beforeyesterday— When I practiced running, my strength _____ and Ifell onto the ground.

Careful study shows that the best athletes win____,_____they think then can win