1.
six (long, thin objects)
A count of six items using the counter 本, which applies to long, thin objects such as pens, bottles, sticks, trees, films, calls, and roads.
ビールを六本買った。
I bought six bottles of beer.
ペンが机の上に六本並んでいる。
Six pens are lined up on the desk.
家の周りには大きな松の木が六本植えられている。
There are six large pine trees planted around the house.
六 (six) + 本 (counter for long, thin items), with sokuon and the regular 本 → 本 change yielding ろっぽん.
SOUND CHANGES WITH 本:
- 一本, 二本, 三本, 四本, 五本, 六本, 七本, 八本, 九本, 十本 / 十本
The ぽん/ぼん/ほん alternation follows the same pattern as other counters using 本.
TYPICAL USES:
- ビール六本: six bottles of beer
- 鉛筆六本: six pencils
- 映画六本: six films
- 電話六本: six phone calls
NOTE: 六本木 (Roppongi, a district in Tokyo) literally means 'six trees' and uses this same counter.