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Indonesian imperative

Ya, that's right. But grammatically, imperative sentence always use (!) behind it. But your sentence is just okay.

right sentences :)

"Tunggu saya disana!" is correct.
But I think it's not polite if you just saying "tunggu saya di sana!"
For me, it's better to say "Tunggu saya disana ya!"
The word "ya" is showing politeness. (It's my opinion, but every Indonesian has different opinion about it. It's up to you want to use it or not)

Actually, In bahasa Indonesia has few type of imperative sentences.
But I will share some of the simple types.

In bahasa Indonesia, the imperative sentence usually supported with the root of the word. e.g "Lihat!"="see!" it means if you see something interesting then you want to told your friend to see it too, you can say it.
"Makan!" = "Eat!"
"Baca bukunya!" = "Read the book!"
"Ayo! pergi!" = "C'mon! Let's go!"
but if you say it with very high intonation, the meaning will be different. Some one will think that you're angry.
e.g:
"Keluar!" = "get out!"

or

you can add the "tolong, mohon, ayo" word. it means "please" in English. Those words more polite to say.
e.g: Tolong bukakan pintu itu! = Open the door please!
Tolong, kamarnya dirapiin ya! =Please clean up your room!
Tolong televisinya dimatikan! = Please turn off the TV!
Ayo, diambil makanannya! Tidak usah malu. => Someone asking you to grab the food in formal situation.
Mohon tenang! = Quite please!

Hope this short explanation will help you :)

itu benar sekali
that's right my brother:)

That is correct but you need punctuation mark "!" when you make a imperative sentence. all verb + "!" can be imperative sentence even without subject in some situation.
ex: Duduk! ; Lari! ; Pergi! (direct conversation)
^_______^