PRESENT SIMPLE - NEGATIVE

1.- Rewrite the sentences below using negative sentences and replacing the underlined words with the ones in brackets. 
Example:

We want to inform you (scare).
We don't want to scare you.

a) A virus contains malicious instructions. (useful information)

b) Viruses spread to other computers. (stay in one computer)

c) A worm sends copies of itself to all the contacts in our e-mail list. (some)

d) Macro viruses infect Word documents. (htm files)

e) Some viruses disguise themselves as funny programs such as a greeting card. (many other)

f) A virus causes a computer to run more slowly. (faster)

g) Viruses try to replicate themselves. (a Trojan horse)

h) Trojan horses collect personal information like passwords. (a common virus)