We call these in Turkish "pekiştirme sıfatları". THIS IS THE MOST IRREGULAR TOPIC OF OUR LANGUAGE. :) Like we had learnt the irregular verbs in English one by one [go-went-gone, fly-flew-flown etc.] or irregular adjectives [child-children, mouse-mice etc.], you will have to learn by heart these adjectives in Turkish, too.

Strenghtened adjectives means "more than ´too´".

namely: hot --> too hot --> extremely hot

Strengthened adjectives are the third step above.

The feature of the noun is emphasized when we strenghten the adjective.

The way is usually this:

1) We copy the first syllable of the word.

2) We put it in front of the word.

3) We put one of the letters "m,p,r or s" between this copied syllable and the word. The irregularness is here. It´s not clear which letters will come.

It is similiar to the suffixes "in-, dis-, un-"¹ suffixes in English. Like they can´t be used for all the adjectives in English, "m,p,r,s"² can´t be used for all the adjectives in Turkish as well.

¹"disthin" for "thick", "unlong" for "short", "unopen" for "close" etc.

²"teptehlikeli" for "tehlikeli", "güsgüvenilir" for "güvenilir" etc.

tehlikeli (dangerous)

güvenilir (1believable, 2safe)

Let´s start with a few examples:

siyah (black)

Let´s take the first syllable: si

si _siyah

simsiyah (extremely black/fully black/quite black)

kırmızı (red)

Let´s take the first syllable: kı

kı_kırmızı

kıpkırmızı (extremely red/fully red)

koca, kocaman (huge)

ko_koca ------>koskoca (extremely huge/quite huge/too huge)

/ko_kocaman-->koskocaman

yalnız (alone, lonely)

ya_yalnız------>yapayalnız (extremely alone/too alone/quite alone)

boş (empty)

bo_boş-------->bomboş (fully empty/too empty)

uzun (long)

u_uzun-------->upuzun (too long/extremely long/quite long)

*"zarzayıf" is preferred much more than other.

**"düpedüz" means "no need to objection/it is completely clear/it can never be denied/...etc." and it is used for the bad situations/events. 

***"taş gibi" means "like stone". It is being likened to a stone.

****"yumuşacık" is preferred much more.

(?)I´m not exactly sure.

I´ll increase the quantity of the examples as long as I remember words.

Odanızı tertemiz görmek istiyorum. (I want to see your room quite clean.)

oda (room), temiz (clean), görmek (to see), istemek (to want)

oda+nız+ı-------------->odanızı (your room)

te_temiz--------------->tertemiz (quite clean)

iste+yor+im------------>istiyorum (i want)

Elektrikler kesilince oda kapkaranlık oldu. (The room became too dark when the electric went out.)