Modals of necessity, prohibition and permission

Hi,

Why not practice modals in these links?

• Exercise 1
• Exercise 2
• Don't Have to and Mustn't

From English File:

• Must, have to, should 1 
• Must, have to, should 2
  

To go over the second conditional work on:

• Type 2 condition
• First conditional and future time clauses 1
• First conditional and future time clauses 2