The revenue from tourism is the biggest single item in the country's invisible earnings.

旅游收入是该国非贸易性收益中最大的单项收入。

《柯林斯英汉双解大词典》

With very little export other than such farm products as tobacco, cotton and fruit, the country earns enough from invisible earnings to pay its needed, growing imports.

除了农产品，如烟草、棉花和水果之外，希腊没有什么出口货，但它从“无形的收益”中挣不少，足够致富所需的一切——日益增长的进口货。

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Exports and imports put together (including "invisible" earnings from tourists, workers' remittances and exports of services) account for approximately half of India's GDP whereas the comparable proportion for China is over 80%.

BBC: Can India's economy overtake China?