Ответ:

1 Leo has never met  an Australian.

2 We have never seen that film.

3 The explorer has been  in a dangerous situation.

4 i have never gone to Africa.

5 My parents have sailed on an ocean.

6 Toby has gotten lost.

7 Larry and Holly have used a camcorder.

8 You have never found a dinosaur.

9 We have lost your homework.

10 Grandma and Grandpa have never sent an email.