1. The robber caught last week is at the mercy (仁慈，宽恕)of the law.
2. Learning English not only increases our knowledge but also broadens our horizons (视野).
3. There is a growing tendency (趋势) among young couples to live with their parents together in Britain.
4. The exploration (探索) of space by Shenzhou Ⅶ has influenced the whole world.
