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- Design of seven flourin propane fire extinction system 七氟丙烷气体灭火系统设计
- seven flourin propane 七氟丙烷
- Lockup regularly occurs at seven o'clock. 夜间关门时间通常是在七点钟。
- She has as many as seven sisters. 她的姊妹有七人之多。
- She won two third places in the seven events. 她在七项比赛中得了两个第三名。
- There are seven continents in the world. 世界上有七大洲。
- The baby weighed seven pounds at birth. 那婴儿出生时重七磅。
- The dinner consists of seven courses. 晚饭有七道菜。
- Four multiplied by seven is twenty-eight. 7乘4等于28。
- He had to support his seven children, to say nothing of his wife and parents. 他要养活自己的七个孩子，更不必说还有妻子和父母了。
- I used to have breakfast at seven. 我总是7点吃早餐。
- A metrical unit consisting of seven feet. 七韵步由七个音步组成的格律单位
- He was composing at the piano at the age of seven. 他7岁时就会钢琴作曲。
- I have seven roommates in my university. 上大学时，我有七个室友。
- He's sailed the seven seas in search of adventure. 他闯荡七大洋去历险。
- I caught seven trout in fifteen minutes. 我十五分钟内捉到七条鳟鱼。
- Propane may also be used as LPG. 丙烷也可用作液化石油气。
- He was paid seven dollars an hour. 他每小时的工资是七元。
- Seven of our planes are missing. 我们有七架飞机下落不明。
- Some insects produce seven or eight broods a year. 有些昆虫一年产七八次卵。
