Spelling, Vocabulary, and Confusing Words

Because many words in English sound or look alike, frequently causing confusion, this list will be very helpful.
PART 1

a vs. an
Rule. Use a when the first letter of the word following has the sound of a consonant. Keep in mind that some vowels sound like consonants when they’re sounded out as individual letters.
Examples:


a finger
a hotel
a U-turn (pronounced You-turn)
a HUD program
a NASA study

Rule. Use an when the first letter of the word following has the sound of a vowel. Remember that some consonants sound like vowels when they’re spoken as individual letters.
Examples:


an FBI case (F is pronounced ef here)
an honor (H is silent here)
an unusual idea
an HMO plan (H is pronounced aitch here)
an NAACP convention (N is pronounced en here)

Deciding whether to use a or an before abbreviations can be tricky. The abbreviation for Frequently Asked Questions (FAQ) causes confusion because it can be pronounced as a word (fak), or one letter at a time (F-A-Q). Using the guidelines above, one would say a FAQ when it is pronounced as one word, and an FAQ when it is pronounced one letter at a time.
accept
except
to agree; to receive
but, with the exception that
ad
add
advertisement
to perform addition
ades
aides
AIDS
aids
fruit drinks
people who help; assistants
acronym for Acquired Immune Deficiency Syndrome
helps, assists
adverse
averse
unfortunate; strongly opposed (refers to things, not people)
Examples: an adverse reaction to the medication
adverse weather conditions
having repugnance (refers to people)
Example: He is averse to a military draft.
advice (noun)
advise (verb)
recommendation
the act of giving a recommendation
affect vs. effect


Rule 1. Use effect when you mean bring about or brought about, cause or caused.
Example: He effected a commotion in the crowd.
Meaning: He caused a commotion in the crowd.
Rule 2. Use effect when you mean result.
Example: What effect did that speech have?
Rule 3. Also use effect whenever any of these words precede it: a, an, any, the, take, into, no. These words may be separated from effect by an adjective.
Examples: That book had a long-lasting effect on my thinking.
Has the medicine produced any noticeable effects?
Rule 4. Use the verb affect when you mean to influence rather than to cause.
Example: How do the budget cuts affect your staffing?
Rule 5. Affect is used as a noun to mean emotional expression.
Example: She showed little affect when told she had won the lottery.
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