[填空题]If a farmer wishes to succeed, he must try to keep a wide gap between his consumption and his production. He must store a large quantity of grain 　________　 consuming all his grain immediately. He can continue to support himself and his family 　________　 he produces a surplus. He must use this surplus in three ways: as seed for sowing, as an insurance 　________　 the unpredictable effects of bad weather and as a commodity which he must sell in order to 　________　 old agricultural implements and obtain chemical fertilizers to 　______　 the soil. He may also need money to construct irrigation 　______　 and improve his farm in other ways. If no surplus is available, a farmer cannot be 　______　 . He must either sell some of his property or 　________　 extra funds in the form of loans. Naturally he will try to borrow money at a low 　________　 of interest, but loans of this kind are not 　________　 obtainable.
A. A．for
B．against
C．of
D．towards