a six-nation discussion的用法和样例：
- His second putt holed him out for a six .
- I used to get up a six in the morning.
- Each one of them does a six hours' spell of duty.
- Whichever you buy,there is a six month guarantee.
- Put two naughts after a six to make six hunmdred.
- His second putt holed him out for a six.