It was only after he explained that I understood why he was so sad.
他解释后，我才明白了他为什么那么难过。
He explained that he had lost his keys.
他解释说他掉了钥匙。
He explained that his friend was a Swede.
他解释道他的朋友是个瑞典人。
He explained that in fact he saw two balls, and hit the inside one.
他解释说其实有看到两个球，然后击中里面那个。
He explained that he was the public relations person for the Humane Society.
他介绍自己是动物保护协会的公共关系人员。
He explained that he had no time.
他解释说他没有时间。
He explained that he might be late.
他解释说他可能会迟到。
He explained that he had been cheated.
他解释说他是上当受骗了。
He explained that he had to leave at once.
他解释说他必须立即离开。
He explained that his train had been delayed.
他解释说他乘坐的火车误点了。
He explained that he might be late due to the traffic.
他解释说由于交通他可能会来晚。
He explained that he could not tolerate life without a car.
他解释说，自己过不了没有车的生活。
He explained that there are legal ways to make money and illegal ways.
他解释了挣钱的合法方式与非法方式。
He explained that he was the commander of a small unit, with around 100 men.
他自称是一个小分队的指挥官，手下大约有100人。
He explained that his plan was so strict that he had to reward himself occasionally.
他解释说，他的计划太严格了，以致于不得不偶尔奖赏自己一下。
He explained that his plan was so strict that he had to reward himself occasionally.
他解释说，他的计划太严格了，以致于不得不偶尔奖赏自己一下。
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