In English, words are made up of roots and affixes. Roots are the basic parts of words that have meaning. Affixes are added to roots to change their meaning or function.

Here are some examples of roots:

Aqua = water

เช่น Aquarium
ฺBio = life

Here are some examples of affixes:

• -er (a person who does something)

• -ing (the act of doing something)

• -ly (in a certain way)

• -less (without)

• -ness (the state of being)

When a root and an affix are combined, they form a new word with a new meaning. For example, the root act and the affix er combine to form the word actor, which means "a person who acts." The root speak and the affix ing combine to form the word speaking, which means "the act of speaking."

Here are some more examples of words that are formed by combining roots and affixes:

• runner (a person who runs)

• carefree (without care)

• freely (in a free way)

• happiness (the state of being happy)

• helpful (able to help)

Learning about roots and affixes can help you to understand the meaning of new words. When you see a new word, you can break it down into its root and affixes. This can help you to figure out the meaning of the word.

For example, the word beautiful is made up of the root beaut (beauty) and the affix ful (full of). This means that the word beautiful means "full of beauty."

Learning about roots and affixes can also help you to spell new words. When you know the root and affixes of a word, you can usually figure out how to spell the word.

For example, the word friendliness is made up of the root friend, the affix li (like), and the affix ness (the state of being). This means that the word friendliness means "the state of being like a friend." You can see that the word friendliness is spelled correctly because it follows the rules for adding affixes to roots.

I hope this explanation of roots and affixes is helpful for Thai students.

Learning Latin and Greek roots can be very helpful for understanding English vocabulary, as many English words are derived from these languages. Here are ten Latin and Greek roots that can be beneficial for non-native English speakers to learn:

Latin Roots:

1. **Bene** - Meaning "well" or "good" (e.g., benefit, benevolent, beneficial)

2. **Mal** - Meaning "bad" or "evil" (e.g., malevolent, malfunction, malicious)

3. **Dict** - Meaning "to say" or "to speak" (e.g., dictate, diction, contradict)

4. **Cred** - Meaning "to believe" (e.g., credible, incredulous, credential)

5. **Mater** - Meaning "mother" (e.g., maternal, maternity, matriarch)

Greek Roots:

6. **Bio** - Meaning "life" (e.g., biology, biography, biome)

7. **Tele** - Meaning "distant" or "far off" (e.g., telephone, television, telepathy)

8. **Graph** - Meaning "to write" or "to record" (e.g., photograph, graphic, biography)

9. **Auto** - Meaning "self" or "automatic" (e.g., automobile, autobiography, autopilot)

10. **Chrono** - Meaning "time" (e.g., chronology, chronic, synchronize)

Learning these roots can help non-native English speakers better understand and decipher the meanings of a wide range of English words and expand their vocabulary.

Root Words with Prefixes: อุปสรรค

1. Unhappiness: "Un-" is the prefix, which makes the word negative or reverses the meaning.

2. Dislike: "Dis-" is the prefix, indicating the opposite or absence of liking.

3. Understand: "Under-" is the prefix, suggesting a lower or lesser degree of comprehension.
Underage = You are an underage.
Underperform =

4. Precook: "Pre-" is the prefix, implying something done in advance.

5. Misinform: "Mis-" is the prefix, signifying incorrect or wrongly given information.
Misfortune
Mistakes

Root Words with Suffixes: ปัจจัย

1. Quickly: "-ly" is the suffix, forming an adverb that describes how something is done.

2. Beautifully: "-ly" is the suffix, indicating the manner in which something is done, in this case, beautifully.
- Slow + ly = slowly

3. Friendship: "-ship" is the suffix, creating a noun indicating the state or quality of being friends.

4. Movement: "-ment" is the suffix, forming a noun that indicates the result of the action, in this case, movement.

5. Happiness: "-ness" is the suffix, forming a noun that represents a quality or state, such as happiness.