"My older brother is twenty years old."
Translation:Abang saya dua puluh tahun.
Technically not; nya is referring to her/his (or the third person). Ibu saya umur lima puluh tahun. Ibu mas Rudi umurnya lima puluh empat tahun. However this is not commonly used this way. Nya is used for possession (tasnya (his/her bag), mobilnya (her/his car)) or in combination with "di" and the third person.
All context and depends where you are (island) as you will refer to most new males you meet with some form of family address to show respect.
Abang is used in Sumatra and many parts of east kalimantan to address another male around your age or older, (pak is used for senior citizens).
the word 'Mass' is used in the same way throughout Java (i didnt hear abang once in a month in java travelling i don't believe, only kakak laki laki for older siblings and mass for addressing)
depending where you travel (main islands) will depend on which one you use in addressing other males or talking about family and which one is used more frequently used, all are known so really it doesn't matter if you use abang or kakak laki laki they wont care in indonesia, each island just has a preference of their own. same can be said with Wanita (woman), perempuan (woman/female) and gadis (girl) depends where you are in the country to which one will be used more frequently, so know all and adapt depending upon on what you hear in each part of the country.
As soon as i got off the ferry from Java to Sumatra i had to change from permissi Mass to permissi abang when addressing males.
Mas is written with one s. In eastern Java "mas" can indeed be used, but they also use "cak" there to address a young man. Everywhere in Java when you see the man in obviously older then you, or if someone with a high position (orang tinggi) and same age/younger then you, then use "pak". Pak can be used safely everywhere in Indonesia and "bu" for a woman.
Preceding nouns, "adalah" menas "to be". This temple is a tourism object. = Candi ini adalah obyek wisata. However it is optional, so it can be skipped. Candi ini obyek wisata. In a formal way you can write: Abang saya adalah dua puluh tahun. The "abangku" is unformal and then a formal use of adalah does not fit in bahasa Indonesia.