Chinese numbers

I need to post here in order to not to forget it. Chinese numbers are easier than I had thought. Or at least the way they are formed beyond ten.
1 一 yī

2 二 èr

3 三 sān

4 四 sì

5 五 wǔ

6 六 liù

7 七 qī

8 八 bā

9 九 jiǔ

10 十 shí

0 零 / 〇 líng

The strokes are taken from the same site I did last time. And now, here's an audio file. It'll make it easier!

Once you know these eleven numbers, counting to up to 99 is easy thing:

11 (10+1) 十一 shíyī

12 (10+2) 十二 shí'èr

13 (10+3) 十三 shísān

19 (10+9) 十九 shíjiǔ

20 (2x10) 二十 èrshí

21 (2x10 + 1) 二十一 èrshíyī

22 (2x10 + 2) 二十二 èrshí'èr

30 (3x10) 三十 sānshí

40 (4x10) 四十 sìshí

90 (9x10) 九十 jiǔshí

99 (9x10 + 9) 九十九 jiǔshíjiǔ

Again, an audio file. Whoever is ready for an exercise, here it is! Or take a quiz!!

Today we also "learned" how to say our date of birth. It'd go something like 我 生日是 1975年 9月6号.