正压式氧气呼吸器供氧系统由哪些部件组成？
参考答案：由高压气瓶、减压器、自动补给阀、手动补给阀、定量孔等部件组成。
The two girls are twins. ____ names are Lucy and Lily. [ ]
A. their
B. They're
C. Their
D. Theirs
输出动物，出境前须经隔离检疫的，在口岸出入境检验检疫机构指定的隔离场所隔离检疫。( )
