Plz solve Ex. 11

Exercise 11. Rewrite the following sentences using the simple past or the present perfect tense of the verbs given in the brackets:
1. The air hostess (lock) the doors of the plane. It is soon going to take off.
2. "You (understand) the lesson? I (bring) some comprehension questions for you to answer. I am sure you will find them quite easy," (say) the teacher.
3. I am sorry I (not see) your water bottle. Perhaps you (leave) it in the playground. When you last (drink) water from it?
4. When I (be) a child, my father (take) me to visit almost all the historical places of Delhi but I (not see) the Red Fort yet.
5. A customer (come) to the shop early in the morning and (buy) four loaves of bread.
6. Your performance in most of the subjects is good. But why (you secure) poor grades in Science?
7. Doctor, I am sorry for disturbing you so early in the morning. My father (suddenly slip) in the bathroom and I am afraid, he (hurt) his right leg.