k you’ve got to the point achange is needed , otherwise you’ll fail

27．Shanghai Expo has been building an Expo Village for the participants, but other choices will also be ____ if the Expo Village does not satisfy their needs．

These old coins were made of________ and they were used in ancient China.

We all know that learning a foreign language _________ time and effort.

to use in April,2005,the road hassolved the long-standing problem of traffic jams of this area．