[译] 她难以下决心。
[误] She was hard to make up her mind.

[正] It was hard for her to make up her mind.
[注] 句中 hard 的逻辑主语应该是 to make up her mind, 而在误句中变成了 she, 所以犯了逻辑错误。应该改用 it 作形式主语的结构。