单选题：Doctors suggest that people should wash their hands .A. twic

题目内容：

Doctors suggest that people should wash their hands .
A. twice a day
B. three times a day
C. four times a day
D. eight times a day

参考答案：

答案解析：

A. tiresome B. hard C. interesting D. easy

分类：英语题型：单选题

23．（16分）在真空环境内探测微粒在重力场中能量的简化装置如图所示。P是一个微粒源，能持续水平向右发射质量相同、初速度不同的微粒。高度为h的探测屏AB竖直放置

分类：英语题型：单选题

----This is your order, a hamburger and an apple pie ___________ ?A. Anything

分类：英语题型：单选题

Business is the organized approach to providing customers with the goods and ser

分类：英语题型：单选题

46. A．exploration B．education C．experiment D．entertainment

分类：英语题型：单选题