1.That young inventor succeeded in making a newer and faster computer_____ the end.
2.You needn't heat the dish _____ a long time.Five minutes is enough.
3.The ancient people usually cooked food or boiled water _____ an open fire.
4.You've been absent for six days according ____ our records.
5.You can find out how this invention works ____ this way.
6.Who was the New World discovered _____?
Columbus ,of course.
7.One of the kids fell _____ the river.We must help him.