[经] economical quantities oil
shù liàng shàng zhí de kāi cǎi de shí yóu ㄕㄨˋ ㄌㄧㄤˋ ㄕㄤˋ ㄓˊ ㄉㄜ˙ ㄎㄞ ㄘㄞˇ ㄉㄜ˙ ㄕˊ ㄧㄡˊ