它们都不是公共的，因为那些未付款者可以被篱笆或路障挡在外面而得不到服务。
Neither is public because those not paying can be prevented from receiving the service—by fences or toll barriers.
它们都不是公共的，因为那些未付款者可以被篱笆或路障挡在外面而得不到服务。
Neither is public because those not paying can be prevented from receiving the service-by fences or toll barriers.
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