A demonstrative is a word which indicates exactly what is being talked about. The most common ones in English are this and that.
The main demonstratives in Japanese are the ko-so-a-do series. Do- words are question words, like which and where.
For the demonstratives to stand alone in a sentence, like “That is bright”, the suffix れ (re) is used after the ko, so, a, or do.
|あれ||are||that (far way)|
どれ(dore) cannot be followed by the は(wa) particle and is followed by the が(ga) particle instead.
Dore desu ka?
Which one is it?
Dore ga anata no pen desu ka?
Which one is your pen?
To be more specific and to add a noun, change the れsuffix to の
|これ kore||この kono|
|あれ are||あの ano|
|どれ dore||どの dono|
れ words must always stand alone.
の words must always be followed by a noun.
この+ noun + wa particle +rest of the sentence
Kono ocha wa oishii desu.
This tea is delicious.
その+ noun + wa particle + rest of the sentence
Sono hana wa kiiro desu.
That flower is yellow.
あの+ noun + wa particle + rest of the sentence
Ano kanojo wa utsukushii desu.
That woman (over there) is beautiful.
(for example purposes, I added the あの but it is not always required in conversation.)
どの+noun + ga particle + rest of the sentence.
Dono hon ga kowai desu ka?
Which book is scary?
To indicate place, れ(re) and の(no) are replaced by こ(ko). However, for the あ series, it’s changed to あそこ (asoko) instead of あこ (ako).
|ここ||koko||here (near me)|
|そこ||soko||there (near you)|
*Any native Japanese speakers, please feel free to make any corrections. This information is based on studying from the Genki series of textbooks (Genki I, 2nd edition).*