Use the verb in the Principle Clause in the Past Tense and make all the necessary changes D. 2. Mother says my brother returned an hour ago.
5. I suppose I saw them at the theatre.
F. 3. He says he'll be preparing for his report in the library. 7. We know they'll be waiting for us at the bus stop.
G. 1. She says she will have finished the translation by the evening. 2. Jane hopes her friend will have received her message by that time.
H. 2. I'm sure they'll come to the party if we invite them. 7. I hope she will help me if I ask her.

During many centuries people all over the world can't imagine their lives without friendship. Friend - is a person, who helps and supports you in any situation/ It is a well-known fact, that practically every person on the Earth found his friends at school/ So why school friendship can be constant?
I personally feel that school ages are the perfect time to make friends. Only then you can live without problems and responsibilities. You can communicate with contemporaries  and get pleasure from it. By the way, children can detect lie and meanness better than adults. That is why, friendship in such a young age is the most sincere.
 But when you grow up, you find new interests, new priorities and old friends lose value in your eyes. Moreover,you and your friends can choose different life's roads and this fact destruct your relationships at all. 
But instead of all facts, you shouldn't forget about the idiom "A friend is never known till needed." No matter how and where you met your friend: at school or university, pab or cafe, you will always detect :your" person, who will be your anchor during the whole life.

1)Im ready.-So am I
2)I study six days a week.-So do I
3)I like swimming.-So do I
4)I've been to Africa many times.-So have I
5)I had lunch very late today.-So did I
6)I can play the violin.-So can I
7)I will go abroad for Christmas.-So will I
8)We've bought a cat!-So have I
9)I have three dogs.-So do I
10)John gets up very early.-So do I
11)I like this weather.-So does Jane
12)My cat loves Whiskas.-So does mine
13)My mother cooked a chicken.-So did my sister
14)I have read this book.-So have we

15)I have seen crocodiles many times.-So has Steve
16)I can speak Spanish.-So can they
17)I have a car.-So does Alice
18)I like this show.-So does my brother
19)I have some money.-So do we
20)I had a lot of work yeaterday.-So did Sam