Choose the verb forms to complete the sentences

1. The brave people
   [defend|defended] their city against the enemy in 1812.
2. Look! Ann
   [does|is doing] her hair.
3. He
   [saw|was seeing] Elen when he
   [crossed|was crossing] the street.
4. He
   [will|shall] be able to phone us when he
   [is|will be] at home.
5. While she
   [was reading|read] a book, her little brother
   [was playing|played].
6. If I
   [leave|will leave] the house at 3 p.m., I
   [arrive|will arrive] at the airport on time.
7. John
   [is|was] never late for his classes. He always comes on time.
8. When he
   [buys|will buy] a computer, John
   [is|will be] able to send e-mails to me.
9. Ask him if Mrs Morgan
   [joins|will join] us for lunch.
10. Peter the Great
    [found|founded] St Petersburg.
11. We
    [don't have|haven't] to get up early in summer.
12. Once she
    [was calling|called] to the office last month.
13. You have recently recovered. Are you sure you
    [will be able to|could] come hiking with us tomorrow?