Where can you put your books?
a bookcase
I must/ mustn't feed my dog every day
MUST
What's this?
a tap
My brother must/ can listen to music
CAN
What's this?
a mirror
You can/must use my phone!
CAN
Where can you do dishes?
a sink
You mustn't/must be loud in the library
MUSTN'T
My sister must/mustn't eat lot of chocolate
MUSTN'T
