1.
The leap year comes around once in four years.
闰年每四年来一次[每四年有一个闰年]。
2.
fourteen years for having attempted to escape on four occasions.
四次企图越狱，十四年。
3.
He had to repeat the fourth grade.
他读四年级时留级一年。
4.
Skip from the fourth to the sixth grade.
从四年级跳级到六年级。
5.
which usually lasts three or four years.
学制是三年或四年。
6.
In 1954, it was changed to a regional level city under Sichuan Province's jurisdiction.
一九五四年改为地级市，由四川省管辖。
7.
The boy was kept back in the fourth grade.
男孩在四年级时留级。
8.
I have lived in the U. S. for four years now,
我在美国生活了四年，
9.
He himself had only finished the fourth grade.
他自己只上完四年级。
10.
November 1946 and April 1947
（一九四六年十一月、一九四七年四月）
11.
March and April,1941, PREFACE
（一九四一年三月、四月）序
12.
commemorate May 4tb Youth Day
纪念“五四”青年节
13.
Forty is the old age of youth, fifty is the youth of old age.
四十是青年的老年，五十是老年的青年。
14.
"Cs..."25th April, 1498.
一四九八年四月二十五日
15.
There are four seasons in a year.They are spring,summer,autumn and winter.
一年有四季，这四季是春、夏、秋、冬。
16.
Thanksgiving Day is on the 4th Thursday in November.
感恩节在每年十一月的第四个星期四。
17.
Reverie of May 4~(th):Remembered the 90~(th) Anniversary of May 4~(th)
遐思“五四”——为纪念五四运动90周年而写
18.
40 Years' Meritorious Service Certificate
四十年优良服务奖状