Change, or the ability to【B1】oneself to a changing environment is essential【B2】evolution.

The farmer whose land is required for housing or industry must adapt himself: he can transfer to another place and master the problems【B3】to it; he can change his occupation, perhaps【B4】a period of training; or he can starve to death. A nation which can't adapt its trade or defense requirements to【B5】world conditions faces an economic and military disaster. Nothing is fixed and permanently stable.【B6】must be movement forward, which is progress of a sort, and movement backward, which is decay and deterioration.

In a changing world, tradition can be a force for good or for evil.【B7】long as it offers a guide, it helps the ignorant and the uninformed to take a step【B8】and, thereby adapt themselves to【B9】circumstances. But if we make an idol of tradition, it ceases to be a guide. It becomes an obstacle【B10】on the path of course. Man is to accept the help which tradition can give but to be well aware of its limitations in a changing world.

【B1】

A．change

B．fit

C．adapt

D．adopt