Complete the sentences with the correct form of the verbs in brackets. Use the present simple or present continuous.

1 Thanks for the explanation. I_______ (understand) the idea now.
2 We ______ (not eat) out very often but we  ______ (go) out to a restaurant tonight because it's my dad's birthday.
3 A What about you? You haven't got your PE kit today?
B It's not that. I ______ (not do) PE this month. I've got a problem with my knee.
A Oh, Is it bad?
B No, not very bad. I mean, it ____ (not hurt) me all the time, but I can't do any serious exercise yet.