Key Takeaways

  • Affect is usually a verb (to influence); effect is usually a noun (result)
  • Their (possessive), there (location), they're (they are) have distinct meanings
  • Its (possessive) has no apostrophe; it's means "it is"
  • I before E except after C (with exceptions like "weird")
  • Double final consonants in CVC words when adding vowel suffixes (stop → stopping)
Last updated: January 2026

Spelling and Commonly Confused Words

The TEAS tests your knowledge of correct spelling and the ability to distinguish between commonly confused words. These skills are essential for clear medical documentation.

Commonly Confused Words

WordMeaningExample
affectVerb: to influenceThe medication will affect her mood.
effectNoun: resultThe medication had a positive effect.
acceptVerb: to receiveShe will accept the diagnosis.
exceptPreposition: excludingEveryone except the patient left.
thenIndicates timeFirst check vitals, then give medication.
thanComparisonThe patient is older than expected.
theirPossessive pronounTheir results are ready.
thereLocationThe chart is over there.
they'reContraction: they areThey're waiting for results.
yourPossessive pronounYour appointment is tomorrow.
you'reContraction: you areYou're scheduled for surgery.
itsPossessive pronounThe hospital updated its policy.
it'sContraction: it isIt's important to wash your hands.
whosePossessiveWhose chart is this?
who'sContraction: who isWho's the attending physician?
toPreposition/infinitiveShe went to the lab.
tooAlso; excessiveThat's too much medication.
twoNumber 2Give two pills daily.

More Commonly Confused Pairs

WordsUsage
lose / looseLose = fail to keep; Loose = not tight
principal / principlePrincipal = main/head of school; Principle = rule/belief
stationary / stationeryStationary = not moving; Stationery = paper supplies
complement / complimentComplement = complete; Compliment = praise
council / counselCouncil = group; Counsel = advice/advisor
cite / site / sightCite = quote; Site = location; Sight = vision
passed / pastPassed = went by (verb); Past = previous time
breath / breatheBreath = noun; Breathe = verb
conscious / conscienceConscious = aware; Conscience = moral sense

Spelling Rules

1. I Before E Rule

  • General: i before e except after c
  • Examples: believe, receive, ceiling
  • Exceptions: weird, neither, leisure, seize

2. Dropping the Silent E

  • Drop e when adding suffix starting with vowel: hope → hoping
  • Keep e when adding suffix starting with consonant: hope → hopeful
  • Exception: judgment, acknowledgment

3. Changing Y to I

  • Change y to i when adding suffix (if y follows consonant): happy → happiness
  • Keep y if suffix starts with i: carry → carrying
  • Keep y if y follows vowel: play → played

4. Doubling the Final Consonant

  • Double when:
    • Word ends in consonant-vowel-consonant (CVC)
    • Word is one syllable OR stress is on last syllable
    • Suffix starts with vowel
  • Examples: stop → stopping, begin → beginning
  • Don't double: open → opening (stress not on last syllable)

Medical Terminology Spelling

WordCommon Misspelling
hemorrhagehemmorage, hemorhage
diarrheadiarhea, diarrea
abscessabcess
occurrenceoccurence, occurance
accommodateaccomodate
necessaryneccessary, necesary
maintenancemaintainance
separateseperate
definitelydefinately
occurredoccured

Strategies for Spelling Success

1. Learn Root Words Understanding roots helps spell related words:

  • "Cardi-" (heart): cardiac, cardiologist, cardiovascular
  • "Derm-" (skin): dermatology, epidermis

2. Use Mnemonics

  • "There" has "here" in it (location)
  • "Stationery" has an "e" like "envelope"
  • "Principal" is your "pal"

3. Sound Out Syllables Break words into parts: ne-ces-sar-y, sep-a-rate

4. Visualize the Word Picture the correct spelling in your mind.

5. Proofread Carefully Spell-check doesn't catch correctly spelled wrong words (their/there).

Test Your Knowledge

Choose the correct sentence.

A
B
C
D
Test Your Knowledge

Which sentence uses "their," "there," and "they're" correctly?

A
B
C
D
Test Your Knowledge

Which word is spelled correctly?

A
B
C
D