Unique rules when forming that grammar are highlighted like this
Example sentences follow these rules too!
Joining and Nesting Markers:
Verb[た/る] - means that dictionary form and ta form are accepted.
Verb[causative[て]] - means て form of the causative form of the verb.
Details
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使用域一般
Information
[Used to express criticism about someone's behavior or regret that something is not possible, which might have been acceptable (or possible) if the subject/case were A]