You ... wear a helmet when you ride a bike.
can't
must
mustn't
You ... use your phone during an exam.
mustn't
don't have to
can
We ... borrow a ball from the school gym if we need one.
can
musn't
have to
The school director ... attend every meeting; her assistant can do it for her.
mustn't
doesn't have to
can't
The goalkeeper ... wear gloves.
can
doesn't have to
has to
We ... play basketball in the library.
can't
must
don't have to
We ... arrive at school before 8:10 a.m.
have to
can't
can
You ... bring your own breakfast; the school provides it.
don't have to
have to
can't
