1·They are highly destructive insect pests.
他们是破坏性极大的有害昆虫。
2·A locust is a kind of destructive insect.
蝗虫是一种害虫。
3·They are highly destructive insect pests that can cause extensive damage to fruit and vegetable crops, trees, shrubs and turf grasses.
它们是具高度破坏力的害虫，会对蔬果作物，树木，灌木以及草坪造成重大损害。
4·The paper reports the results of survey on different species of destructive insect against bamboo and wood in 135 spots of Chengdu region from 1994 to 1997.
我们自1994～ 1997年对成都市范围内各区县的竹木用材蛀虫危害情况进行了初步调查。