Obligation
Guests _____ take the visitor's card everytime they get into the building.
Must
Employees _________ to surf the web inside the building. It's prohibited.
Are not allowed to / Mustn't (Because they can)
Anyone _________ wear any type of suit, as long as it's decent-looking. It's part of the uniform.
Is allowed to
Walk in the hospital ______.
quietly
I ______ finish this report before Friday!
Need to (because it is a necessity)
You _______ talk like that at the office! They'll fire you!
Can't
The president _______ talk in behalf of the company as long as it's good for everyone.
is allowed to
Listen to your classmates ______.
respectfully
I ______ meet with the representative today, to conclude the report.
Have to
The CEO _______ let that opportunity pass. It will benefit the entire company.
Mustn't
Employees _______ bring their own stuff to the office.
are allowed to / can
Students can ask questions ______ in this class.
freely