Look at the sentences in Exercise 4. Then rules with should or shouldn't. We use . to say something is a good idea. We use to say something isn't a good idea. Grammar reference • page 116​

I have just a few illnesses so i am a lucky person. I have tonsillitis, but just when my body is cooled, so usually  i have it in the winter. The other illnesse is chickenpox, i think that almost all people had this. I remeber that it was very difficult don't touch  my body, because i had itch, and i wanted always to scratch my wounds. About tonsillitis i can say that i have always very high temperature and my voice is  hoarse. Also my nose is stuffed. So sometimes too difficult to say something.