四十倍的 meaning in English

forty fold
fortyfold

Aedes mosquitoes are characterized by white stripes on their bodies but these are barely visible to the naked eye . ovitraps also attract other insects to lay eggs . therefore we have to magnify the larvae under a stereomicroscope for proper identification
白纹伊蚊蛹的特点是带有白纹，但凭肉眼是看不出来，加上诱蚊产卵器又会吸引其他昆虫产卵，故需以十至四十倍的放大镜来检视。