英文错句改错!说明一下错的理由!

1.Since that journey,I never sailed again.
句子里有Since,表示持续一段时间；则必须用对应持续时间的时态= 完成时,所以用have done.
（Since that journey,I have never sailed again.）
2.I'd rather prefer just to lie on the beach.
would rather 和 prefer to 意思冲突了,重复了.【去掉prefer 和 to】【去掉 'd rather】二选一
（ I'd rather just lie on the beach.）（I prefer just to lie on the beach.）
3.She began to think she was becoming mad.
think 感觉不妥,可能换成 feel 更合逻辑.think = 思考的想,feel =认为,感觉到
（She began to feel she was becoming mad.）
4.Both the husband and the wife aren't reliable.
两个都否定用 Neither ...nor...,然后是单数 is
（Neither the husband nor the wife is reliable.）
5.The headphones on my new walkman is great.
这里是说 【耳机很棒】,headphones are great,因为耳机是复数.
（The headphones on my new walkman are great.）
6.The teacher told us to see what he was doing.
told （tell) 是告知,告诉.【老师告诉我们去看看他在做什么】在这里不合逻辑,应该换成 asked.
（The teacher asked us to see what he was doing.）
7.Her beautiful blond hairs were shining in the sun.
hair 作为 【头发】讲的时候,是单数hair,同时 were 也就不对了,要用 was
（Her beautiful blond hair was shining in the sun.）
8.They will steal all your money and valuable things.
这个没问题.
感觉 money 和 valuable things 可以并存.【除非认为 money 属于 valuable things ,这太勉强吧】

请问是每句都错吗？因为我只有看到很明显的一句：
2. I'd rather just lie on the beach. 不需要 prefer 因为 I'd rather 本身就有「我宁可」的意思，