序数词是: thirtieth，缩略形式:30th
By sunset we had covered thirty miles.
到日落时我们已走了三十英里。
Some thirty people attended the funeral.
大约有三十人参加了葬礼。
She thinks nothing of walking thirty miles a day.
她认为一天步行三十英里不足为奇。
She's in her mid-thirties—thirty-six to be exact.
她三十五岁左右—确切地说是三十六岁。
When March comes to the thirtieth day.
三月正当三十日。
A day is about one thirtieth of a month.
一天大约是一个月的三十分之一。
The thirtieth on the list is a young man.
名单上第三十个人是个年轻人。
