Correct

七十

/ qī shí / 
Strokes

Definition

seventy/70

Example

As a Numeral

seventy

1
Tā
他
kuài
快
qīshí
七十
suì
岁
le
了
  
。

He is in his late sixties./He is about seventy.

2
Dìqīshí
第七十

seventieth

3
Qīshíjǐ
七十几
suì
岁
de
的
rén
人

septuagenarian

4
Qīshí
七十
niándài
年代

(in) the seventies; (in) the'70s; (in) the 1970s