Building such a bridge over the bay was ______,but the local government made it within two years.( )
a wet blanket
a piece of cake
a dark horse
a hard nut to crack
Jack is a great talker. It's high time that he ________ something instead of just talking.
It is necessary that the government solutions for the problems of air pollution to create a clear environment.
We lost our way in that small village, otherwise we________ more places of interest yesterday.
If we _______ adequate preparations, the conference wouldn’t have been so successful.
Without the development of the Internet, Taobao and Tmall______$ 5.7 billion in sales on 11 November, 2013.