Activity 5. Define non/identifying relative clauses. Put commas where necessary.
1) The criminal who stole personal details of thousands of Internet users was finally caught yesterday.
2) Paul downloaded a malicious program which infected his computer with a virus.
3) Someone stole my credit card details which were used to pay for things on the Internet.
4) What is being done at the moment to stop cyber criminals who steal money?
5) People who commit crimes using computers are called computer hackers.
6) Hackers who break into computer systems with malicious intent steal sensitive information.
Activity 6. Combine two sentences using relative pronouns and adverbs:
1) Virus is a computer program. It can make copies of itself.
2) That’s the man. His computer was crashed because of a virus.
3) Hacker is a person. He gets into someone else's computer system without permission to do something illegal.
4) Malicious program is any computer program. It is designed to harm its victim(s).
5) Harassment is behavior. Its aim is to trouble or annoy someone.
6) There is a backdoor to the computer. It can be used to steal data.
7) The Internet is a global system. You can find a lot of information there.
Activity 7. Put the following adjectives in the correct column:
authorized, legal, safe, secure, advertent, trusted, reliable, known, faithful, authentic, disguised, protected, altered, intentional, violate, offensive, limited, damaged, dependent