Задание 1

1. My friends were invited to the party by me.

2. The house was painted by John last week.

3. The Grand Canyon is visited by thousands of tourists every year.

4. These machines are used by chefs to mix the ingredients.

Задание 2

1. To play/playing - оба варианта можно

2. Watching

3. Skating

4. To be

5. To find