The correct answer would be helping verbs. The helping verbs are combined with the main verbs to indicate time, possibility and other kinds of meaning. The helping verbs' function is to help extend the meaning of the main verbs by adding more detail on it. Helping verbs are very essential in the formation of different tenses of the verb.
We have been waiting for an hour
1) <span>Banquo and Macbeth enter. Banquo addresses the witches--they do not look like normal inhabitants of the earth and have beards. They in turn hail Macbeth as Thane of Glamis, then Thane of Cawdor, finally as future king. Banquo wonders why Macbeth starts at their words, and asks what they would prophecy for him, though he is less concerned than Macbeth with what they have to say: "If you can look into the seeds of time / And say which grain will grow and which will not, / Speak then to me, who neither beg nor fear / Your favors nor your hate."
2)</span><span>Back in Scotland, at </span>Macbeth's<span> castle in Dunsinane, a doctor waits with one of Lady </span>Macbeth's<span> gentlewomen. They're keeping an eye out for Lady </span>Macbeth's<span> sleepwalking, which the gentlewoman reported began once </span>Macbeth<span> left to prepare the house for battle.
3)</span><span>Yes, because some people's lives are living tragedies. Sure, times and living conditions aren't as hard as they used to be for most, but some people invite tragedy into their lives and some poor souls seem to be cursed with it. One person that comes to mind is Jackie Hance, whose drunk sister-in-law murdered Jackie's three young girls.
Reference: </span>https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwih7crP_qHQ...
Yes they can if they want