allied ·adjective
Definition: joined by a formal agreement Level: C2
战争期间，同盟国密切协调了他们的军事战略。
During the war, the ___allied powers coordinated their military strategies closely.
海军的首要任务是保护同盟国的航运线路免受潜艇袭击。
The navy’s primary mission was to protect ___allied shipping lanes from submarine attacks.
这两家公司通过一份正式的合作伙伴协议结成联盟，以开发新技术。
The two companies became ___allied through a formal partnership agreement to develop new technology.