仔细阅读下面的短文，短文中有10个空格或画线句子。请按照每小题括号内的具体要求完成语法填空、词形变化、句子合并、句子改写以及病句改正等。

　　Electronic mail(e-mail)　　1　　(start)in the late 1960s by the U．S．military．By the 1980s, academics in a number of fields were using e-mail for professional collaboration．The early 1990s 　　2　　(see)an explosion of the use of e-mail and other computer networking tools for a wide range of professional, academic, and personal purposes．

　　E-mail is a way of 　　3　　(send)a message from one computer to one or more other computers around the world．First, you 　　4　　(短语动词)the e-mail address of the person you are sending the message to．Then you write the message, or 　　5　　(direct)in a special e-mail software program or first in a word processing program and transfer it into the e-mail software．You should push a button 　　6　　 a simple command to send the message．The computer system you are connected to will break the message up into tiny pieces and send them 　　7　　(electronic)to the destination．The pieces might travel numerous routes through other computers on the way．Usually within 2-3-minutes, the pieces will all arrive at their destination, where the 　　8　　(receive)computer will reassemble them into a message．The person 　　9　　 the message can check his or her mailbox at a 　　10　　(convenience)time and read the mail．

阅读下面短文，根据上下文填入适当的词语，或使用括号中词语的适当形式，并将答案填写在1～10的相应位置。

　　Electronic mail(e-mail)　　1　　(start)in the late 1960s by the U．S．military．By the 1980s, academics in a number of fields were using e-mail for professional collaboration．The early 1990s 　　2　　(see)an explosion of the use of e-mail and other computer networking tools for a wide range of professional, academic, and personal purposes．

　　E-mail is a way of 　　3　　(send)a message from one computer to one or more other computers around the world．First, you 　　4　　(短语动词)the e-mail address of the person you are sending the message to．Then you write the message, or 　　5　　(direct)in a special e-mail software program or first in a word-processing program and transfer it into the e-mail software．You should push a button 　　6　　(give)a simple command to send the message．The computer system you are connected to will break the message up into tiny pieces and send them 　　7　　(electronic)to the destination．The pieces might travel numerous routes through other computers on the way．Usually within 2～3 minutes, the pieces will all arrive at their destination, where the 　　8　　(receive)computer will reassemble them into a message．The person 　　9　　(receive)the message can check his or her mailbox at a 　　10　　(convenience)time and read the mail．