The document lists the cardinal numbers in Japanese from 0 to 20 in both romaji and kanji scripts. It explains that numbers from 11 to 19 combine the character for 10 (jyu) with the individual digits (ichi, ni, san, etc.) to represent the teens.

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4. English Japanese Cardinal Numbers in Romaji Kanji
0 rei [rei] 零
1 Iti [ichi] 一
2 ni 二
3 san 三
4 Shi 四
5 go 五
6 roku 六
7 nana 七
8 hati [hachi] 八
9 kyu 九
10 jyu 十
11 jyu ichi 十一
20 ni jyu 二十

5. 11 is 10 + 1 = 11 [ jyu ichi ]
12 is 10 + 2 = 12 [ jyu ni ]
13 is 10 + 3 = 13 [ jyu san ]
14 is 10 + 4 = 14 [ jyu shi ]
15 is 10 + 5 = 15 [ jyu go ]
16 is 10 + 6 = 16 [ jyu roku ]
17 is 10 + 7 = 17 [ jyu nana ]
18 is 10 + 8 = 18 [ jyu hatchi ]
19 is 10 + 9 = 19 [ jyu kyu ]