1、澳大利亚的悉尼用英文是Sydney。英[sɪdnɪ] 美[sɪdnɪ] ；n.悉尼（澳大利亚一城市）。

2、[例句]：He could have died after developing deep vein thrombosis during a flight to Sydney.他在一次飞往悉尼的航行中得了深静脉血栓，险些丧命。