obligate

We were obligated to attend the opening ceremony.

我们有必参加开幕式。

Microsporidia are obligate intracellular parasited eukaryotes.The range of hosts included invertebrate and vertebrate.The microsporidian species parasited mainly fishes and insects.

摘微孢子虫为一绝内寄生之真核生物，寄主范围包含无脊椎动物及脊椎动物，主是以鱼类及昆虫的微孢子虫为主。

Based on different soil corrosion factors and pipe corrosion principle, obligated current negode protection and sacrifice anode protection can be used here.

根据不同的土壤腐蚀因素以及管道腐蚀原理，可以采用强制电流阴极保护和牺牲阳极的阴极保护。