( air forces)
Frequency: The word is one of the 3000 most common words in English.
An air force is the part of a country’s armed forces that is concerned with fighting in the air.
...the United States Air Force...
N-COUNT
( air forces)
Frequency: The word is one of the 3000 most common words in English.
An air force is the part of a country’s armed forces that is concerned with fighting in the air.
...the United States Air Force...
N-COUNT
Collins COBUILD Advanced Learner's English Dictionary. Английский словарь Коллинз COBUILD для изучающих язык на продвинутом уровне. 2006