题意。raise“举起”；understand“理解”；announce“公布；宣布”。
2．people have planted a great many trees in order to __________ wind and sand in the desert.
a．hold down b．hold up
c．hold back d．hold out
解析：选c。hold down资源难易程度:★★★★★★★★★★★★★★★
高考资源网版权所有 ©2005-2010
未经许可，盗用或转载本站资料者，本站将追究其法律责任！
