In October 2001, the Office of the Secretary of Defense acquired both of the existing Predator B prototypes, which were subsequently designated as the MQ-9.是什么意思_In October 2001, the Office of the Secretary of Defense acquired both of the existing Predator B prototypes, which were subsequently designated as the MQ-9.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句