填空题：One of the challenges to build an interactive digital textb

题目内容：

One of the challenges to build an interactive digital textbook from the ground up is that is takes a great deal of ________.

参考答案：【答案仅供学习，请勿对照自行用药等】

答案解析：

How did Becker feel about taxation?

How did Becker feel about taxation?A．He was pleased he only had to pay little．

分类：英语四级题型：填空题

具有溶血作用的苷类化合物为A．蒽酯苷 B．黄酮苷 C．三萜皂苷 D．香豆素苷 E．强心苷

分类：英语四级题型：填空题

The passage is mainly about__________．A．the potential effect of air pollution

分类：英语四级题型：填空题

颗粒状或粉末状，色红明亮，有闪烁的光泽，触之不染手，习称A．“珠宝砂” B．“镜面砂” C．“豆瓣砂” D．“钉头” E．“硬滑石”

分类：英语四级题型：填空题

西红花主产于A．西班牙、意大利 B．山东、河南 C．坦桑尼亚、印度尼西亚 D．浙江、江苏 E．河南、四川

分类：英语四级题型：填空题