20.1.2 Modal verbs and compound tenses II

The English version of compound tenses with modal verbs has follows the logic that the modal verb is put after the subject and the compound tense is unchanged appended with the infinitive form of 'to have' and the perfect participle.

subject + modal verbs + infintive of to have + perfect participle
  He should have known
  He could have been
  He must have done

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