移动互联网业务感知测试APP包含哪几类工作模式（）
A.业务测试模式
B.业务监测模式
C.插件模式
D.APP应用模式
参考答案：A, B
The first textbooks _______for teaching English a foreign language came out in the 16th century.[ ]
A. having written
B. to be written
C. being written
D. written
试述化妆水的作用？
