1.       My friends went to experience the beauty of Mount Kilimanjaro last year, didn`t they?

2.       Did my friends go to experience the beauty of Mount Kilimanjaro last year?

3.       Did my friends go to experience the beauty of Mount Kilimanjaro last year or month?

4.       Who went to experience the beauty of Mount Kilimanjaro last year?

5.       When did my friends go to experience the beauty of Mount Kilimanjaro?