The fourth class is the test class: ServiceClassTest. (the nature of the implementations has been simplified as much as possible.)

第四个类是测试类：ServiceClassTest(实现的性质已经被尽可能地简化)。

youdao

The buses used to test are a common sleeper bus and a high-level sleeper bus riding on the second to the fourth class roads, as well as on the highway.

公路卧铺客车卧姿乘客振动试验分别用普通公路卧铺客车和高档公路卧铺客车在二级到四级公路及高速公路上进行。

youdao

Our class was studying the Gold Rush, something all California fourth graders learned.

我们班正在学习淘金热，加州所有四年级学生都学过这部分内容。

youdao

Next week, from February 7-10 in ceremonies open to the public, the Hall inducts its fourth class in the imposing Roman amphitheater Altos de Chavon in La Romana near the resort Casa de Campo in the eastern part of the island.

FORBES: Honoring Latin Baseball Players--And Jackie Robinson--In The Latin Baseball Hall Of Fame

Audacious is the fourth of the seven Astute Class submarines being built for the Royal Navy.

BBC: HMS Audacious: MoD announces ?1.2bn submarine contract

And fourth-class is the Coptic female.

CENTERFORSECURITYPOLICY: Center For Security Policy