he said :" I could swim when i was very yong" 若对怎么变间接引语

问题描述:

he said :" I could swim when i was very yong" 若对怎么变间接引语

这句话对,除了打字错误yong---->young
he said he could swim when he was very young我想问一下 为什么这里的 was 不往后退一个时态直接变间接不应该变时态吗不必,为什么若原句为一般现在时:he says :" I could swim when i was very yong",改成间接引语,还是he says he could swim when he was very young,对吗?还是有点不明白