这种病毒首先(攻击)人体的免疫系统。

The virus ___attacks the body's immune system first.

去年冬天，一种神秘的疾病袭击了那个小村庄。

A mysterious illness ___attacked the small village last winter.

某些类型的霉菌会(侵袭)呼吸系统，导致严重的健康问题。

Certain types of mold can ___attack the respiratory system, causing serious health problems.