Question

My dictionary A.has lost B.is missing 为什么选B，我就不明白A怎么了，老师说不是丢了，而是描述事实？

下一句是I have looked for it everywhere but still haven‘t found it.

Answer 1

A改成has been lost就通顺了，字典是被丢has been lost或不见is missing，不能自己丢has lost

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lost的主语为什么是人？

Answer 2

如果lose做动词: lose-->lost-->lost, 那么:
I have lost my dictionary.

如果lost是形容词:
My dictionary is/was lost.

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是动词，lost的主语为什么是人？

追答

lose(v.)--to be unable to find (something or someone) (someone)找不到(sth.)=丢失了(sth.)
She's always losing her gloves.
The police lost him in the crowd.

Answer 3

这是半句吧，这个要结合语境的

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下一句是I have looked for it everywhere but still haven‘t found it.