1.不定冠词与序数词连用表示“再一次/个”；
When I finished speaking，a sixth stood up.
我结束后，又一人开始发言。（前面已有五人发言）（不用the）
She failed five times in the match，but she decided to try a sixth time.
她比赛中失败了五次，但是她决定再试一次。（即第六次）
He tried a sixth time and succeeded.
他又试第六次，结果成功了。
有时也表示“六分之一”：
The company yesterday shed a sixth of its workforce.
这家公司昨天裁掉了1/6的员工。
In 2030, a sixth of the country's potential work force could be totally uneducated ．
2030年,该国可能有六分之一的潜在劳动力完全没有受过教育。
2.定冠词与序数词连用表示特指的“第几次/个”。
This is the sixth time that he has failed in the match.
这是他第六次在比赛中失败了。
By 22nd November the Sixth Army was encircled.
到11月22日，第六军被包围了。
In Tokyo share prices have plummeted for the sixth successive day
东京股价已连续第6天猛跌。
It is the sixth month in a row in which imports have fallen.
这是进口量持续下降的第6个月了。
The sixth blind man went forward to feel the elephant.
第六个瞎子走上前去摸大象。
When I got called to Mr. Ratcliff's office for the sixth time, I had no idea what I had done.
当我第六次被叫到拉特克利夫先生的办公室时,我不知道我做了什么。
