Lesson53 Hot snake
    At last firemen have put out a big forest fire in California. Since then, they have been trying to find out how the fire began. Forest fire are often caused by broken glass or by cigarette ends which people carelessly throw away.Yesterday the firemen examined the ground carefully, but were not able to find any broken glass. They were also quite sure that a cigarette end did not start the fire. This morning, however, a fireman accidentally discovered the cause. He noticed the remains of a snake which was wound round the electric wires of a 16,000-volt power line. In this way, he was able to solve the mystery. The explanation was simple but very unusual. A bird had snatched up the snake from the ground and then dropped it on to the wires. The snake then wound itself round the wires. When it did so, it sent sparks down to the ground and these immediately started a fire..
    4、Yesterday the firemen examined the ground carefully, but were not able to find any broken glass.
    昨天，消防隊(duì)員仔細(xì)檢查了地面，但沒有發(fā)現(xiàn)任何碎玻璃。
    語(yǔ)言點(diǎn) were not able to find表示“沒有發(fā)現(xiàn)”。
    5、They were also quite sure that a cigarette end did not start the fire.
    他們還十分肯定火災(zāi)也不是由煙頭引起的。
    語(yǔ)言點(diǎn) sure的三種用法：1) sb. be sure of某人確信；2) sb. be sure to do某人相信能夠去做某事；3 ) sb. be sure that某人確信
    6、This morning, however，a fireman accidentally discovered the cause.
    然而今天上午，一個(gè)消防隊(duì)覓偶然發(fā)現(xiàn)了起火的原因。
    語(yǔ)言點(diǎn) 辨析：三個(gè)常見的表示“發(fā)現(xiàn)”的詞：1) find偶然發(fā)現(xiàn)，碰到；2) find out查明小悄的真相；3) discover找到鮮為人知的事物。