You ............ pay for the bag. It's free (not necessary)
don't have to
I was afraid that I..................be late. (Positive. Possibility. Not sure)
might
You................ drink alcohol. (Negative. Advice)
shouldn't
You............park here. (Negative. Prohibition/ don't have permission)
must not/ can't
He.............have arrived yesterday. (Positive. Possibility. Not sure.)
might
You................ do more exercise. (positive. Advice)
should
They ........... be at home. I saw their car in the garage. (100% sure)
must
We ................. walk the dog. (Positive. Obligation)
must/ have to
You.......... listen to the teacher. (positive. Advice)
should
People....... waste food. (Negative. Advice)
shouldn't/ should not
A: Can I play now, mum? B: No. You..................finish your work. (Positive. Obligation)
must/ have to
I................ play videogames tomorrow. I don't have to work. (Positive. Possibility. Not sure)
might
I .................wash the car today. I washed it yesterday. (Negative. Not necessary).
don't have to
You............. enter the supermarket without a mask. (Negative. Prohibition/ don't have permission)
can't/ must not