Vocabulary — Modals, Affixes, Context Clues & Word Usage - Cheat Sheet
Your last-minute revision companion for mastering vocabulary concepts essential for CSE Professional and other major Philippine exams. Quick reference for the most tested grammar and vocabulary topics.
Modal Verbs
Important facts
- Modal + base form of verb (no 'to')
- No -s in third person singular
- Could have + past participle = past possibility not realized
- Should have + past participle = past advice not followed
- Must expresses stronger obligation than should
- May is more formal than can for permission
- Shall with I/we for offers and suggestions
Key definitions
Modal Verbs
Example
can, could, may, might, must, should, will, would, ought to, shall
Auxiliary verbs expressing modality: possibility, ability, permission, obligation, and advice
Can/Could
Example
I can swim / I could swim when I was young
Ability (present/past), possibility, permission
May/Might
Example
May I leave? / It might rain tonight
Permission (formal), possibility (may = higher, might = lower probability)
Must/Should
Example
You must follow rules / You should study harder
Must = strong obligation/certainty; Should = advice/expectation
Diagrams to know
- Modal functions chart
- Degrees of certainty scale
- Obligation strength hierarchy
Affixes (Prefixes and Suffixes)
Important facts
- Common prefixes: anti- (against), de- (opposite), dis- (not), en-/em- (cause to)
- Common suffixes: -able/-ible (can be done), -tion/-sion (act/process), -ness (state of)
- Negative prefixes: un-, dis-, in-, im-, il-, ir-, non-
- Verb suffixes: -ize, -ify, -ate
- Noun suffixes: -ment, -ness, -ity, -er/-or
- Adjective suffixes: -ful, -less, -ous, -ive
- Remember spelling changes when adding suffixes
Key definitions
Prefix
Example
un- (unhappy), re- (rewrite), pre- (preview)
Word element attached to the beginning of a word to modify meaning
Suffix
Example
-able (readable), -ment (agreement), -tion (education)
Word element attached to the end of a word to form another word
Negative Prefixes
Example
un-, dis-, in-, im-, il-, ir-, non-, anti-
Prefixes that create opposite meanings
Diagrams to know
- Prefix meaning chart
- Suffix function table
- Word formation tree
Context Clues
Important facts
- Four main types: synonym, antonym, inference, definition/description
- Signal words for contrast: but, however, although, while, instead, on the contrary
- Signal words for definition: that is, commas, dashes, parentheses
- Look for cause-and-effect relationships
- Consider the overall tone and setting
- Pay attention to punctuation marks as clues
Key definitions
Context Clues
Example
The acrid smell made our eyes water (acrid = unpleasant)
Hints in surrounding text that help determine meaning of unfamiliar words
Synonym Clues
Example
heinous crime from which he will never recover (heinous = wicked)
Words nearby with same or similar meaning
Antonym Clues
Example
garrulous, but most hardly talk (garrulous = talkative)
Words showing opposite meaning using signal words
Definition Clues
Example
Playing volleyball exacerbated his injury. It aches more (exacerbated = worsened)
Direct explanation of the word within the sentence
Diagrams to know
- Context clue types flowchart
- Signal words reference chart
Correct Usage and Troublesome Words
Important facts
- Its = possessive; It's = it is
- Your = possessive; You're = you are
- There = place; Their = possession; They're = they are
- Accept = receive; Except = exclude
- Advice = noun; Advise = verb
- Between = two items; Among = more than two
- Fewer = countable; Less = uncountable
- Principal = main/head; Principle = rule/belief
Key definitions
Homophones
Example
there/their/they're, your/you're, its/it's
Words that sound alike but have different meanings and spellings
Amount vs Number
Example
amount of water vs number of books
Amount = uncountable quantities; Number = countable items
Affect vs Effect
Example
The rain affected the game / The effect was postponement
Affect = verb (to influence); Effect = noun (result)
Diagrams to know
- Commonly confused words chart
- Usage decision tree
Must remember
- Modal + base verb (no 'to', no -s)
- Could have/Should have + past participle for unrealized past
- Context clues: synonym, antonym, definition, inference
- Signal words: but, however (antonym); that is, dashes (definition)
- Its vs It's: possessive vs contraction
- Affect = verb, Effect = noun
- Between (2 items) vs Among (3+ items)
- Principal = person/main, Principle = rule
- Fewer (countable) vs Less (uncountable)
- Prefixes change meaning, suffixes often change part of speech
Last minute tips
- For modals: If unsure between can/may, choose may for formal permission
- Context clues: Read the ENTIRE sentence, not just around the word
- Homophones: Sound it out in your head - does the meaning make sense?
- Prefix/suffix questions: Break the word into parts and define each part
- When choosing between similar words, consider the formality level required
Comparison tables
Modal Verb Functions
| Modal | Ability | Permission | Possibility | Obligation |
|---|---|---|---|---|
| Can | Present ability | Informal permission | General possibility | No |
| Could | Past ability | Polite request | Lower possibility | No |
| May | No | Formal permission | Higher possibility | No |
| Might | No | Very polite request | Low possibility | No |
| Must | No | No | Strong certainty | Strong obligation |
| Should | No | No | Expectation | Advice/weak obligation |
Context Clue Types
| Type | How It Works | Signal Words | Example |
|---|---|---|---|
| Synonym | Same meaning words nearby | None specific | heinous crime, wicked act |
| Antonym | Opposite meaning shown | but, however, although | garrulous, but hardly talks |
| Definition | Direct explanation given | that is, commas, dashes | exacerbated - it aches more |
| Inference | Use logic and background | None specific | acrid smell made eyes water |
Commonly Confused Word Pairs
| Word 1 | Meaning 1 | Word 2 | Meaning 2 | Memory Trick |
|---|---|---|---|---|
| Affect | Verb - to influence | Effect | Noun - result | A for Action (verb) |
| Accept | To receive | Except | To exclude | Accept = receive ALL |
| Principal | Main person/thing | Principle | Rule or belief | Principal = PAL (person) |
| Its | Possessive pronoun | It's | It is/it has | It's has apostrophe for IS |
| Your | Possessive pronoun | You're | You are | You're = you ARE |
Diagrams
Complete Vocabulary Concepts Overview
Mind map showing all major vocabulary concepts and their relationships for quick review
Context Clues Strategy Flowchart
Step-by-step process for identifying and using different types of context clues to determine word meanings
Modal Verb Certainty Scale
Visual representation of how modal verbs express different degrees of certainty from impossible to certain