Modals Can and Must

These are 2 essential verbs

To practise their forms and use, try these Interactive books:

Can

Must

Some more Practice: 

Can('t): 1, 2, More interactive exercises

Must(n't): 1, 2, 3, 4, More

Can and Must: 1, 2
PLAY Modal Moonshot
Totally unrelated to Modal Verbs, but...:
Read about TOMATOES and THE TOWN OF CLARKSON

Finally, a couple of videos for you

Easy:

Harder (includes other Modals):

Looking forward to hearing from you!