It's very dangerous for us _____ the mobile phone while crossing the street.
本题考查句式结构。句意：对我们来说，过马路的时候接听手机是很危险的。根据“It's + adj. + for sb. + to do sth.”的句式结构可知答案为B。
用所给词的适当形式填空。
You(promise) to take our boy to Disneyland last year. Don't let him down again.
根据 last year 可知，时态是一般过去时，故所缺的词是promised。
—Simon failed the exam again.
—That's not surprising. Computer games _____ too much of his time.
本题考查 take 短语的用法。四个选项的含义分别是：take in 吸收；take on 呈现，承担；take off 起飞，脱掉；take up 占用，开始从事。根据本题语境可知，Simon 考试又没有及格，电脑游戏占用了他太多的时间，故答案为D。