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secondary system | |||
associated system | |||
ancillary system | |||
auxiliaries system | |||
accessory systems | |||
subsystem | |||
accessory system; backup system | |||
auxiliary system; satellite system | |||
subordinate system; support system; supporting system | |||
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accessory system | |||
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auxiliary system |
辅助 系统: 521 phrases in 46 subjects |