Question

几个关于数词的问题

1.xx世纪xx年代怎么说?
比如20世纪80年代,是in 1980s/in the 1980s/in 1980'/in the 1980'还是别的?
2.He began to work there____.
A. on his fifty B. at age of fifty C. when he fifty D. in his fifties

Answer 1

1980s of the 20th Century 或者80s of the 20th Century

2.He began to work there____. （A）

Answer 2

1.druing the 80s of the 20th century
during the eighties of the twentieth century

2.B