模仿文本：  

Anthrax is a potentially deadly disease that caused by a bacteria. Occasionally it is found in nature but the strain found in the letters is the aim strain developed by the USmilitary after the World War II to research biological weapons and shared with only a few allies. The FBI already suspects that this is a deliberate biological attack.

Anthrax  |'ænθræks| n. 炭疽，炭疽热

Strain 菌株