1.Ray Tomlinson sent the e-mail for the firt time in 1971.的同义句为：
The e-mail was sent by Ray Tomlinson for the firt time in 1971.
2.Thirty students are included in the Music Club.的同义句为：
The Music Club includes thirty students.
3.People wrote numbers in many different ways many,many years ago.的同义句为:
People wrote numbers in many different ways long long ago.
4.Our school has 48 classes.的同义句为:
There are 48 classes in our school.