çok / az / biraz

1. Çok (Much / Many / Very)
This is the most common intensifier. It can mean 'many' with countable nouns, 'much' with uncountable nouns, or 'very' with adjectives. It can also modify verbs to show intensity (e.g., Seni çok seviyorum - I love you very much). A common alternative for countable items is birçok (many/a lot of). Note that birçok is always written as one word.

• Çok su (Much water)
• Çok elma (Many apples)
• Çok güzel (Very beautiful)

2. Az vs. Biraz (Little vs. A Bit)
The distinction between these two is based on nuance:

• Az: Implies a negative or insufficient amount. 'I have little money' (not enough).
• Biraz: Implies a neutral or positive amount. 'I have a bit of money' (enough for a coffee).

3. Countability Rules
While biraz is technically for uncountable nouns (like milk or time), it is often used for 'some' of a whole. For specifically counting a few items, the word birkaç is often preferred. Like birçok, the word birkaç is always written as one word. Biraz is also very common for degree (e.g., biraz yorgun - a bit tired).

4. The Singular Rule
In Turkish, when a quantifier like çok, az, biraz, birçok, or birkaç is used, the noun must remain in the singular form. It cannot take the plural suffix, even if the meaning is plural. This same rule applies to numbers (e.g., üç elma, not üç elmalar) and the word her (every). However, the noun can still take case endings like the dative or locative.

Note: The primary exceptions to this singular rule are the words bazı (some) and bütün (all). These words usually require the plural suffix when referring to a group of items (e.g., bazı insanlar - some people; bütün öğrenciler - all the students). Bütün only takes a singular noun when referring to a single whole unit (e.g., bütün gün - the whole day).