Here are the sentences in the present perfect tense:
1. Ernie has broken his leg four times.
2. I have never flown a kite.
3. Has your brother ever eaten snails?
4. Our friends haven't played volleyball this month.
5. Has he borrowed your pen?
6. My father has never read romantic books.
7. I haven't seen Julia this morning.
8. Has Mrs. Salwick ever written a book?
9. My family has lived in this town for 6 years.
10. Has your grandma ever ridden a bike?
**Explanation:**
The sentences are formed using the structure 'subject + have/has + past participle'. Adverbs like 'never', 'ever' and time indicators like 'this month' or 'this morning' are used with the present perfect. In questions the auxiliary 'have/has' is put before the subject.