Dua pasang suami istri.
Two married couples.
Bambang membeli dua pasang burung dara.
Bambang buys two pairs of pigeons.
Pasang also refers to inanimate objects that come in pairs such as shoes, socks, wings (but not – as in English – trousers/pants, scissors, or spectacles/eyeglasses).
Saya membeli tiga pasang sepatu.
I buy three pair of shoes.
Pasang can also denote a set:
Dewi membeli dua pasang meja kursi sekaligus.
Dewi bought two sets of tables and chairs at once.
A pasangan is something/someone that is coupled/the other part of a pair:
Di mana pasangan sepatu itu?
Where is the other shoe?
Rudi pasangan menarimu?
Is Rudi your dancing partner?
Akiko dan Joe sudah menjadi pasangan.
Akiko and Joe are a couple now.
Most interesting, and most challenging, is the verb memasang, which basically means “to pair”, “to match”, or “to fit” , and hence also “to install”.
Dia memasang ac di rumah. He installed an air-conditioning unit in his house.
Besok saya harus memasang ban baru. Tomorrow I have to put on new tires.
Saya memasang bintang penghargaan di dadanya. I pin the medal on his chest.
Jangan lupa memasang bola lampu. Don’t forget to fit the light bulb.
Here are more examples. Note that the underlying idea is always that two things are matched to another (like the curtain is matched with the rod, the printer with the computer, the advertisement with the media in which it is placed, the fire to the candle, etc.)
memasang lilin, to light a candle
memasang api, to light a fire
memasang sepatu, to put on shoes
memasang tali sepatu, to tie one’s shoes
memasang printer, to connect a printer
memasang gorden, to hang up curtains
memasang iklan, to place an advertisement.
memasang kemah, to set up a tent
memasang kancing, to button up
memasang telinga, to sharpen one’s ears, listen carefully
memasang mesin, to install a machine
memasang pakaian, to put on clothes
memasang saluran tivi, to turn on a television channel
memasang pagar, to build a fence
memasang bendera, to hang out the flag
memasang layar, to set sails
memasang tarif/harga, to set a fare/price
memasang pengumuman, to post an announcement
memasang radio, to turn on the radio
memasang aksi, to show off
memasang taruhan, to place a bid