四级考试是许多童鞋必须通过的考试，其重要程度不言而喻。希望通过四级听力天天练，童鞋们可以提高听力水平，高分通过四级，冲刺六级。
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听力原文：
Passage Three
When my interest shifted from space to the sea, I never expected it would cause such confusion among my friends. Yet I can understand their feelings. As I have been writing and talking about space flight for the best part of 20 years, ____1____ To explain, I'd like to share my reasons behind this unusual change of mind. The first excuse I give is an economic one. Underwater exploration is so much cheaper than space flight. ____2____ By the end of this century, the cost will be down to a few million. On the other hand, the diving suit and a set of basic tools needed for skin-diving can be bought for 20 dollars. ____3____ The ocean, surprisingly enough, has many things in common with space. In their different ways, both sea and space are equally hostile. If we wish to survive in either for any length of time, we need to have mechanical aids. The diving suit helped the design of the space suit. ____4____
a sudden switch of interest to the depth of the sea does seem peculiar.
The first round-trip ticket to the moon is going to cost at least 10 billion dollars if you include research and development.
My second argument is more philosophical.
The feelings and the emotions of a man beneath the sea will be much like those of a man beyond the atmosphere.