In the earliest stages of man’s development he had no more need of money than animals have. He was content with very simple forms of shelter, made his own rough tools and weapons and could provide food and clothing for himself and his family from natural materials around him. As he became more civilized, however, he began to want better shelter, more efficient tools and weapons, and more comfortable and more lasting clothing than could be provided by his own neighborhood or by the work of his own unskilled hands. For these things he had to turn to the skilled people such as smiths, leather workers or carpenters. It was then that the question of payment arose.
练习1 Exchange of goods became difficult because _________.
A: man became more civilized
B: smiths began to look after land or cattle in their spare time
C: more and more goods which had no fixed exchange values came to the marker
D farmers hadn’t enough grain or meat to provide for skilled workers
2 Money was not used until _______.