识读器
参考答案：
是利用射频技术读取标签信息，或将信息写入标签的设备
Don't be _____ by products ______ to make you look slim quickly. [ ]
A. taken away; promised
B. taken in; promised
C. taken out; promising
D. taken in; promising
病例对照研究的优点与局限性是什么？
