听力原文:Tom, just to say "Well done". I thought you raised your points just the right moment. Someone needed to ask that question, and I think you put it very well.
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A strong El Nino can last two or three years ______.
______tells you how to alternate your speed to smooth your driving.
Dave bought Stella the puppy to ____
According to the passage the worst disease for human population is______.
He refused to sit for the examination, _____ (这是蠢事一桩).