从A、B、C、D四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
21、The tour will provide unique opportunity for to live with British family for a week in hope that you will have a better understanding of the UK.
A．a；不填 B．an；不填 C．a；the D．an；the
22、—The fellow has been suspected e-mail fraud．
—Nowadays cyber crime is developing an amazing rate．
A．from：at B．about；in C．of；with D．of；at
