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今天我们要学的词是random。 Random, 是随机、任意的意思。The firefighters have to undergo a random drug test once a year, 消防队员每年要接受一次是否服用毒品的抽查。The boxer refused to submit random blood tests...
今天我们要学的词是random。 Random, 是随机、任意的意思。The firefighters have to undergo a random drug test once a year, 消防队员每年要接受一次是否服用毒品的抽查。The boxer refused to submit random blood tests...
Americans who smoke are beginning to feel unwanted as federal laws prevent them from smoking in public buildings The World Health Organizations says smoking is considered a high risk factor in six of the eight leading causes of death worldwide. Medic...
This is Scientific Americans 60-Second Science. Im Steve Mirsky. Got a minute? Ever been woken up by the sound of the refrigerator compressor kicking on? Well, such clumsy heat exchange units featuring long metal coils may be on their way out. Becaus...
This is Scientific Americans 60-Second Science. I am Cynthia Graber. This will just take a minute. Ants are known for working together, operating as a unit for the good of the colony. But not so fast, say researchers from the Universities of Leeds an...
