有错,
1.that somethings I know 看似宾语从句, 可是没有谓语, know 是定语从句的谓语
2. 有后置定语修饰,特指意味,最好不用something , 而用the thing
3. something 没有复数形式
参考：
I don't want to admit the thing (that)I know
=I don't want to admit what I know
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