Which modal verbs do we use to express obligation? And no necessity?
Must and have to / Don't have to
Which modal verb do we use to express something is a rule or an obligation?
MUST
Carol must finishes her homework for tomorrow.
Carol must finish her homework for tomorrow.
You _____ take your password when you travel abroad.
must
TRUE OR FALSE?
Have and don't have to is used to say something is a rule
FALSE!
Its used to say something is or isn't necessary.
You don't had misbehave in class yesterday.
You didn't have to misbehave in class yesterday.
She _____ answer all the call phones at work every day.
has to
Students _____ late to school.
mustn't be
Do she have to play the guitar at the concert?
Does she have to play the guitar at the concert?
Put the words in the correct order: be / I / on / time / must
I must be on time
Put the words in the correct order: you / if / mustn't / eighteen / are / drive / under / you
you mustn't drive if you are under eighteen
Parents not must let their children miss school.
Parents must not let their children miss school.
Explain the use of the modal: My sister must work everyday at 8.
Internal obligation
Explain the function of the modal: Students mustn't speak while they are taking an exam
Prohibition
They must come to the party at 8? Yes, must they.
Must they come to the party at 8? Yes, they must.