Answer:
1. cantan
2. habla
3. practico
4. miramos
5. observaste
6. nadanos
7. baila
8. trabajan
9. levanto
10. caminan
explanation
all of the words you have to use in correct form, end with -ar. It helps a lot if you make yourself an example for a word that ends like that so you can understand how to form it right next time. Here:
example for Hablar
I - Yo - Hablo
You - Tú - Hablas
She/He/It - Ella/El/usted - Habla
We - nosotros - Hablamos
You - Vosotros - Hablais
They - Ellos/ustedes - Hablan