Do we have to investigate the subject when we write verbs in future progressive or perfect tenses?
a.
No, because helping verbs for future progressive and perfect tenses are applicable to all subjects.


b.
Yes, because there are helping verbs that are best used when we have specific kinds of subject.


c.
Yes, because that's what the rule in using helping verbs suggests so we should follow strictly.


d.
No, we must investigate on the direct object of the sentence instead of the subject.