fourth

名词 fourth:

1. following the third position; number four in a countable series
2. one of four equal parts
   同义词：one-fourth, quarter, fourth part, twenty-five percent, quartern
3. the musical interval between one note and another four notes away from it

形容词 fourth:

1. coming next after the third and just before the fifth in position or time or degree or magnitude
   同义词：4th, quaternary

副词 fourth:

1. in the fourth place
   同义词：fourthly

1. I can't do the fourth and fifth questions but I've done all the others.
   第四题和第五题我不会，但是剩下的我都答了。
2. After her fourth child she decided to be/have herself sterilized.
   她生了第四个孩子後决定做绝育手术。
3. Mars is the fourth planet in order from the sun.
   火星是太阳系的第四颗行星。
4. Time is sometimes called the fourth dimension.
   时间有时被称为第四度空间。
5. One fourth of a yard; nine inches.
   四分之一码; 九英寸
6. I am a soldier of the fourth cavalry.
   我是第四骑兵部队的一员。
7. One fourth of a ton;500 pounds. Used as a measure of grain.
   五百磅四分之一吨; 五百磅。用作谷物计量单位
8. After her fourth child she decided to have herself sterilized.
   她生了第四个孩子后决定做绝育手术。

fourth

n.（名词）
The ordinal number matching the number four in a series.
第四：一序数词，一列数中的第四个
One of four equal parts.
四分之一
Music
【音乐】
A tone four degrees above or below a given tone in a diatonic scale.
第四音级：自然音阶中高于或低于一给出音调四度的音调
The interval between two such tones.
四度音程：两音调之间的间歇
The harmonic combination of these tones.
四度和音：音调的和谐组合
The subdominant in a scale.
下属音
The transmission gear or gear ratio used to produce forward speeds next higher to those of third in a motor vehicle.
第四档：海车换挡时从第三挡换到下一挡，以加快速度
Fourth The Fourth of July; Independence Day.
Fourth 美独立纪念日：7月4日；美国独立纪念日

来源：
Middle English fourthe
中古英语 fourthe
from Old English fôorth3 * see k wetwer-
源自 古英语 fôorth3 *参见 k wetwer-

【引伸】
fourth
adv.（副词）
adj.（形容词）