vt.

1. 集中；聚集，集结[O][（+on/upon）]
   We must concentrate our attention on efficiency.

   我们必须把注意力集中在效率上。

   Our population is concentrated in the big cities.

   我国人口集中在大城市里。

2. 浓缩

vi.

1. 集中；聚集，集结[Q]
2. 全神贯注；全力以赴[（+on/upon）]
   She couldn't concentrate on a book very long.

   她不能长时间专心读一本书。

n.

1. 浓缩物；浓缩液[C][U]

v.

1. (often concentrate on) focus all one's attention on something.
2. bring together in numbers or a mass in one place.
3. increase the strength of (a solution).

n.