18．On a summer day，Joe invited his friends to supper．He was cooking some delicious food in the kitchen．Suddenly，he （41）found （find） that he had run out of salt．So Joe called to his son，"Go to the village and buy some salt，but pay a fair price for it：neither too much（42）nor too little．"
His son looked surprised．"I can understand why I shouldn't pay too much，Father，but if I can pay less，（43）why not save a bit of money？"
"That would be a very （44）reasonable（reason）thing to do in a big city，but it could destroy a small village like ours，"Nick said．
Nick's guests，（45）who had heard their conversation，asked why they should not buy salt more cheaply if they could．Nick replied，"The only reason a man would sell salt（46）at a lower price would be because he was desperate for money．And anyone who took advantage of that situation would be showing a lack of respect（47）for the sweat and struggle of the man who worked very hard to produce it．"
"But such a small thing couldn't （48possibly （possible） destroy a village．"
"In the beginning，there was only （49）a very small amount of unfairness in the world，but everyone added a little，always，（50）thinking （think） that it was only small and not very important，and look where we have ended up today．"
