1.concentrate on 集中;全神貫注于
They will concentrate on teaching the basics of reading, writing and arithmetic.
他們將集中教授閱讀、寫作和算術基礎知識 。
They should concentrate on rejuvenating the existing vegetation, like grass and shrubs.
他們應該側重于修整現有的綠化植被,比如草和灌木 。
2.at least 至少;最低限度
Try to eat at least four slices of bread a day.
每天盡量至少吃4片面包 。
At least three British golf courses are now owned by the Japanese.
現在英國至少有3家高爾夫球場為日本人所有 。