Add prefixes to the following words to make opposites

How to Make Opposite Words Using Prefixes
In English, we can often change the meaning of a word to its opposite by adding a prefix. A prefix is a group of letters added before a word. Common prefixes used to form opposites are:
- un- (e.g., unhappy)
 - in-, im-, il-, ir- (e.g., incorrect, impossible, illegal, irregular)
 - dis- (e.g., disagree)
 - non- (e.g., nonverbal)
 
Let’s look at each word and make its opposite by adding a suitable prefix. Then, we’ll see three more examples using the same prefix pattern.
(a) Comfortable → Uncomfortable
- Prefix used: un-
 - Meaning: Not comfortable
 
More examples:
- Happy → Unhappy
 - Fair → Unfair
 - Safe → Unsafe
 
(b) Necessary → Unnecessary
- Prefix used: un-
 - Meaning: Not necessary
 
More examples:
- Wanted → Unwanted
 - Known → Unknown
 - Clear → Unclear
 
(c) Like → Dislike
- Prefix used: dis-
 - Meaning: To not like
 
More examples:
- Agree → Disagree
 - Appear → Disappear
 - Connect → Disconnect
 
(d) Valid → Invalid
- Prefix used: in-
 - Meaning: Not valid
 
More examples:
- Active → Inactive
 - Complete → Incomplete
 - Visible → Invisible
 
(e) Regard → Disregard
- Prefix used: dis-
 - Meaning: To have no regard or concern
 
More examples:
- Obey → Disobey
 - Trust → Distrust
 - Approve → Disapprove
 
