"This is the valid price."
Translation:Ini harga yang berlaku.
"Yang" can be use for many situation as a conjuction.
- For pointing the next sentence after the "yang" word
Eg. Orang yang baik hati (A kind hearted person)
- Give an explanation to the next sentence to refer the previous sentence.
Eg. Seorang kakek yang duduk di halte itu sedang menunggu taksi (The old man sit on that bus station is waiting for a taxi)
In this sentence: Ini harga yang berlaku
It shows the validity of a specific price.
The price there is unchangeable.
I think there is a subtle difference. If I was bargaining over the price, the seller might say, Ini harga berlaku = This is the (valid) price ... meaning that this is the price I will offer. Ini harga yang berlaku would be what would be said if I queried the price ... e.g. Is this the price with the discount? I may be wrong, but 'yang' usually adds some specific meaning ... but not always.
"Ini harga berlaku" would translate "This is the price is valid," and is ungrammatical. "Ini harga yang berlaku" (the best solution) translates "This is the price that is valid" (note that "yang" is mandatory because "berlaku" is a verb). An alternative might be "Harga ini berlaku," but that translates "This price is valid" which is unfaithful to the original sentence as "This" is the subject in the original rather than "This price."
No, "yang" is mandatory. Without it, the sentence becomes "This is the price is valid." If you really wanted to remove "yang," I think you would have to also remove "ber-" as it derives the verb "berlaku" from "laku," but I am uncertain of the full implications this would have as I don't really know what "laku" alone means.
"Ini harga yang berlaku" translates "This is the price that is valid;" note the order of "Ini" relative to "harga." Your proposed solution of "Ini yang harga berlaku" would translate to "This that is the price is valid" which, while technically grammatical, would be unfaithful to the original sentence (and probably strange?).
You're repeating the subject twice, which is redundant. Translating "ini harganya berlaku" would form "this its price is valid". The suffix "-nya" makes the word it's attached to refer to the possessor (like a possessive noun). If you want to use "-nya", then the sentence has to be changed into just "Harganya berlaku". However, you would need another sentence to clarify what you want to refer to in front of the new sentence. For example, "Ini sebatang pen yang murah. Harganya berlaku." Of course, I speak Malay and not Indonesian so there might be slight inconsistencies in language.