1. What Are Modal Verbs?

Browser selection: Each browser has its own security measures in place, but some can have serious flaws that allow hackers and cybercriminals to exploit and invade. Ensure that you're using a secure browser to reduce the risk of compromising your computer or network.

Multi-factor authentication (MFA): MFA is a method of controlling computer access by requiring several separate pieces of evidence to an authentication mechanism. Websites and email accounts can be made more secure by requiring at least two factors of authentication by a user.

Email security: Email creates a wave of opportunity for viruses, worms, Trojans, and other unwanted programs. Establishing a multi-layered and comprehensive email security strategy will help significantly reduce exposure to emerging threats. Email messages can also be protected by using cryptography, such as signing an email, encrypting the body of an email message, and encrypting the communication between mail servers.

Firewalls: Firewalls act as filters that protect devices by allowing or denying access to a network. By applying a specific set of rules to identify if something is safe or harmful, firewalls can prevent sensitive information from being stolen and keep malevolent code from being embedded onto networks.

9.Relative Clauses

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  This handout will help you understand what relative clauses are and how they work, and will especially help you decide when to use “that” or “which.”
  
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  What is a relative clause?
  
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  A relative clause is one kind of dependent clause. It has a subject and verb, but can’t stand alone as a sentence. It is sometimes called an “adjective clause” because it functions like an adjective—it gives more information about a noun. A relative clause always begins with a “relative pronoun,” which substitutes for a noun, a noun phrase, or a pronoun when sentences are combined.
  
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  The relative pronouns are: