Degrees of Adjectives
Comparatives and superlatives are constructed in a very straightforward way in Turkish. Besides these, there is a special way of making adjectives stronger in Turkish and this is not very trivial. I this lesson, we will cover all these topics.
1. Comparatives
1.1. More, Less
Comparative of an adjective is obtained by adding the word "daha" before the adjective. We can say that daha is the word for more and all adjective comparatives are constructed like 'more clever' (not like faster).
faster --> daha hızlı
slower --> daha yavaş
more intelligent --> daha zeki
more hardworking --> daha çalışkan
more beautiful --> daha güzel

If you want to say less beautiful or less hardworking, then replace the word 'daha' with 'daha az'.
less fast --> daha az hızlı
less intelligent --> daha az zeki
less hardworking --> daha az çalışkan
less beautiful --> daha az güzel

Now, let's see how the comparative form of an adjective is used in sentences.
I am beautiful. --> (Ben) güzelim.
I am more beautiful. --> (Ben) daha güzelim.
You are more beautiful. --> (Sen) daha güzelsin.
She is more beautiful. --> (O) daha güzel.

This is a fast car. --> Bu hızlı bir araba.
This is a faster car. --> Bu daha hızlı bir araba.
This car is faster. --> Bu araba daha hızlı.

1.2. More than
If you want to compare two nouns with respect to an adjective, the structure used in English is as follows:
noun1 is more adjective than noun2
Ex1: Ahmet is more hardworking than Mehmet.
Ex2: I am more intelligent than you.
The structure to express the same meaning in Turkish is as follows:
noun1 noun2-den daha adjective
Ex1: Ahmet Mehmet'ten daha çalışkan. (Note that the ' sign is used to separate private names from their suffixes)
Ex2: Ben senden daha zekiyim.

Now, let's see a few example sentences with this expression.
- Beril is beautiful. --> Beril güzel.
- Gökçe is more beautiful. --> Gökçe daha güzel.
- Gökçe is more beautiful than Beril. --> Gökçe Beril'den daha güzel.
- He is more hardworking than me. --> O benden daha çalışkan.
- My car is faster than your car. --> Benim arabam senin arabandan daha hızlı.
- US is larger than Turkey. --> Amerika Türkiye'den daha büyük.

1.3. As ... as
If you want to say that two nouns are equal with respect to an adjective, the strıctıre used in English is:
noun1 is as adjective as noun2
Ex1: Beril is as beautiful as Gökçe.
Ex2: I am as beautiful as you.
The structure to express the same meaning in Turkish is as follows:
.noun1 noun2 kadar adjective
or
noun1 de noun2 kadar adjective
Both of these expressions have the same meaning, you will understand the very slight difference as you see them used. One point to note here is that if noun2 is a simple pronoun (like ben, sen, bu, şu) then it is used in possessive form (like benim, senin, bunun, şunun).
Ex1: Beril de Gökçe kadar güzel.
Ex2: Ben de senin kadar güzelim.
Now, let's see a few example sentences with this expression.
- Beril is beautiful. --> Beril güzel.
- Gökçe is also beautiful. --> Gökçe de güzel. (de means 'also', 'as well')
- Gökçe is as beautifl as Beril. --> Gökçe de Beril kadar güzel.
- He is as hardworking as me. --> O da benim kadar çalışkan.
- My car is as fast as your car. --> Benim arabam da senin araban kadar hızlı.
- US is almost as large as China. --> Amerika neredeyse Çin kadar büyük. (neredeyse means almost)

2. Superlatives
Superlatives are also straightforward in Turkish, like it is in English. Instead of 'the most', you use 'en', and all superlatives are constructed using this word.
the fastest --> en hızlı
slower --> en yavaş
the most intelligent --> en zeki
the most hardworking --> en çalışkan
the most beautiful --> en güzel

Now, let's see how the superlative form of an adjective is used in sentences.
I am beautiful. --> (Ben) güzelim.
I am more beautiful. --> (Ben) daha güzelim.

When you want to use the superlative form in a sentence, there are two different cases:
I am the most beautiful. --> (Ben) en güzelim. (This has the meaning of describing yourself, like an answer to the question "What are your traits?")
I am the most beautiful. --> En güzel benim. (This has the meaning of the answer to the question "Who is the most beautiful?")

I am the most beautiful girl. --> En güzel kız benim.
I am the most beautiful girl in this class. --> Bu sınıftaki en güzel kız benim.
You are the most beautiful girl in this class. --> Bu sınıftaki en güzel kız sensin.
She is the most beautiful girl in this class. --> Bu sınıftaki en güzel kız o.

3. Making an adjective stronger
3.1. Very
In English, when you want to make an adjective stronger, you use the word 'very'. Saying very fast is a stronger statement than just saying fast. The same method is applied also in Turkish, and the word for very is 'çok'. Hence:
very fast --> çok hızlı
very slow --> çok yavaş
very intelligent --> çok zeki
very hardworking --> çok çalışkan
very beautiful --> çok güzel
You are very beautiful. --> (Sen) çok güzelsin.
She is a very beautiful girl. --> (O) çok güzel bir kız.
This girl is very beautiful. --> Bu kız çok güzel.
3.2. Too
Another way of making an adjective stronger, but this time giving the meaning extreme, is to use the word too. Saying something is too fast gives the meaning that it is extremely fast and should be slower. The word for too in Turkish is 'fazla'.
too fast --> fazla hızlı
too slow --> fazla yavaş
too intelligent --> fazla zeki
too hardworking --> fazla çalışkan
too beautiful --> fazla güzel
We are too fast. --> (Biz) fazla hızlıyız.
This car is too fast. --> Bu araba fazla hızlı.
3.3. Other ways
A third way commonly used in Turkish (which is not seen in English) to make an adjective stronger is adding a modified form of the first syllable before the adjective. Important points to note here are:
There is not a rule for how this first syllable should be modified, which makes this rule hard to learn.
This gives the same meaning as using the word 'very' and makes the adjective stronger.
All adjectives can't be made stronger using this method, and there is not a rule to understand for which adjectives this method can be used. A group of adjectives you can always use this method is colors, to express that the color is strong. However, there is no rule to exactly say which adjectives can be made stronger like this.
Because there is not a well-defined rule, it will be very difficult to go over adjectives and see what the stronger form of each adjective is. I think you should not try to learn this for each adjective at this step. The best strategy here would be to note that there is a rule like this and when you see it used, you will understand what it means. In your sentences, you simply can use 'çok + adjective' instead and you will be clearly understood.
Let's see some examples to this rule:
hızlı --> fast
hıphızlı --> very fast
sarı --> yellow
sapsarı --> very yellow, strong yellow
mavi --> blue
masmavi --> very blue, strong blue
beyaz --> white
bembeyaz --> very white, strong white
çabuk --> quick
çarçabuk --> very quick
kalın --> thick
kapkalın --> very thick

Another way to make an adjective stressed and stronger is to repeat it twice. Again, this is not done with all adjectives and the best way to learn for which adjectives this rule is applicable is to note when you hear an adjective used like this. Don't be afraid by these rules, you will learn how to use them if you start reading Turkish texts or if you speak to native speakers. You can still express yourself without using these methods for making adjectives stronger. Simply use the word 'çok' before the adjective. I am giving these rules now so that you know the meaning when you see such a usage somewhere.
büyük büyük evler --> big houses, the property big is stressed
sarı sarı elmalar --> yellow apples, the property yellow is stressed

There is also another way to stress an adjective and make it stronger. That is, adding a modified form of the adjective after the original form. This is again an irregular rule and you don't need to know this completely, just understand it when you see this usage. Sometimes, an adjective followed by the modified form of that adjective may have a slightly different meaning.
yaşlı --> old (for people)
yaşlı başlı --> old, mature
eski --> old (for objects)
eski püskü --> very old and useless