新概念英语第三册Lesson42课堂笔记

Lesson 42 Modern cavemen Listen to the tape then answer the question below.With what does the writer compare the Gouffre Berger? Cave exploration, or pot-holing, as it has come to be known, is a relatively new sport. Perhaps it is the desire for solitude or the chance of making an unexpected discovery that lures people down to the depths of the earth. It is impossible to give a satisfactory explanation for a pot-holer's motives. For him, caves have the same peculiar fascination which high mountains have for the climber. They arouse instincts which can only be dimly understood. Exploring really deep caves is not a task for the Sunday afternoon rambler. Such undertakings require the precise planning and foresight of military operations. It can take as long as eight days to rig up rope ladders and to establish supply bases before a descent can be made into a very deep cave. Precautions of thissort are necessary, for it is impossible to foretell the exact nature of the difficulties which will confront the pot-holer. The deepest known cave in the world is the Gouffre Berger near Grenoble. It extends to a depth of 3, 723 feet. This immense chasm has been formed by an underground stream which has tunnelled a course through a flaw in the rocks. The entrance to the cave is on a plateau in the Dauphiné Alps. As it is only six feet across, it is barely noticeable. The cave might never have been discovered had not the entrance been spotted by the distinguished French pot-holer, Berger. Since its discovery, it has become a sort of potholers' Everest. Though a number of descents have been made, much of it still remains to be explored. A team of pot-holers recently went down the Gouffre Berger. After entering the narrow gap on the plateau, they climbed down the steep sides of the, cave until they came to a narrow corridor. They had to edge their way along this, sometimes wading across shallow streams, or swimming across deep pools. Suddenlythey came to a waterfall which dropped i