他回答说：“亲爱的爸爸，今年我学会了青蛙叫的含义。”
He answered, "Dear father, I have this year learnt what the frogs croak."
奇怪的蛙叫般的声音有可能是别国潜水艇无意发现的。
The strange frog like sounds may have been emitted by the foreign submarines unintentionally.
第三，蛙叫声来自别国潜水艇的想法也是站不住脚的。
Third, , the idea that the quackers were caused by a secret submarine from another country does not hold up.
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