1. It is difficult to locate a tree typical of a pure species in the arboretum and park collections of the United States and Europe. 当你在美国和欧洲的树木园或公园采集时，很难找到一株典型的纯种树。
2. The ability of natural enemies to control the pests in Arboretum which is in suburb and better management level are the strongest and can cut down the pests species amount effectively. 捕食性天敌在时间上能有效跟随害虫并控制其危害。地处市郊、管护措施较好的植物园天敌昆虫对害虫的控制能力最强，能有效地减少害虫的种群数量。
3. Frankly speaking, the arboretum was so spacious that most students were not able to find their ways without the guidance, but it is enjoyable for us to immerse somehow into this wonderland. 坦白的说，庞大的植物温室园让大部分同学失去了方向，不过能沉浸在这片充满生气的世界里也是非常之享受的。
英英解释
n.
1. a facility where trees and shrubs are cultivated for exhibition
