3. Write out countable nouns
chalk, water, paint, backpack, ruler, rubber, dress, brush, cheese, glue, dictionary,
paper, felt-tip, juice, education, college, rule, glass, music

Sure! Here is the answer with detailed explanation:

Countable nouns are the objects or things that can be counted. In the given list of words, we need to identify the countable nouns. Countable nouns can be singular or plural.

1. Chalk - Countable noun. This is an object that can be counted. We can have one chalk or many chalks.

2. Water - Uncountable noun. Water is a substance and cannot be counted in the same way as objects. We cannot say "one water" or "two waters."

3. Paint - Countable noun. It refers to a substance used for coloring and can be counted. We can have one paint or many paints.

4. Backpack - Countable noun. A backpack is a physical object that can be counted. We can have one backpack or many backpacks.

5. Ruler - Countable noun. A ruler is a tool used for measuring and can be counted. We can have one ruler or many rulers.

6. Rubber - Countable noun. It refers to an eraser and can be counted. We can have one rubber or many rubbers.

7. Dress - Countable noun. A dress is an item of clothing that can be counted. We can have one dress or many dresses.

8. Brush - Countable noun. A brush is a tool used for painting or grooming and can be counted. We can have one brush or many brushes.

9. Cheese - Uncountable noun. Cheese is a food substance and cannot be counted in the same way as objects. We cannot say "one cheese" or "two cheeses."

10. Glue - Uncountable noun. Glue is a substance and cannot be counted in the same way as objects. We cannot say "one glue" or "two glues."

11. Dictionary - Countable noun. A dictionary is a book that can be counted. We can have one dictionary or many dictionaries.

12. Paper - Uncountable noun. Paper is a material and cannot be counted in the same way as objects. We cannot say "one paper" or "three papers."

13. Felt-tip - Countable noun. A felt-tip is a type of pen and can be counted. We can have one felt-tip or many felt-tips.

14. Juice - Uncountable noun. Juice is a liquid and cannot be counted in the same way as objects. We cannot say "one juice" or "three juices."

15. Education - Uncountable noun. Education is a concept or process and cannot be counted in the same way as objects. We cannot say "one education" or "two educations."

16. College - Countable noun. A college is an institution that can be counted. We can have one college or many colleges.

17. Rule - Countable noun. A rule is a guideline or regulation and can be counted. We can have one rule or many rules.

18. Glass - Countable noun. A glass is a physical object that can be counted. We can have one glass or many glasses.

19. Music - Uncountable noun. Music is a form of art and cannot be counted in the same way as objects. We cannot say "one music" or "two musics."

So, the countable nouns from the given list are: chalk, paint, backpack, ruler, rubber, dress, brush, dictionary, felt-tip, college, rule, and glass.