ascertains的中文翻译是什么意思

VERB（尤指经过努力后）查明，弄清，确定

If you ascertain the truth about something, you find out what it is, especially by making a deliberate effort to do so.

• Through doing this, the teacher will be able to ascertain the extent to which the child understands what he is reading...

  这样一来，老师就能确定孩子们对他所读的内容理解多少了。

• Once they had ascertained that he was not a spy, they agreed to release him...

  一旦确认他并非间谍，他们即同意将他释放。