[填空题]
Proofread the given passage on ANSWER SHEET TWO as instructed.
For a {{U}}wrong{{/U}} word, underline the wrong word and write the correct one in the blank provided at the end of the line.
For a {{U}}missing{{/U}} word, mark the position of the missing word with a"∧"sign and write the word you believe to be missing in the blank provided at the end of the line.
For an {{U}}unnecessary{{/U}} word, cross the unnecessary word with a slash "—" and pat the word in the blank provided at the end of the line.

Begun in the late 1960s by Pentagon weapons researchers as a system for easing
communication between computers in disparate electric networks, the Internet has evolved (1) ______
into a popular vehicle for scientific research, communication, entertainment, and more. It
links together thousands of computer networks such as those belonging to corporations, (2) ______
commercial se