How to differentiate the visible goods and invisible goods?

Question

用英文回答

Answer 1

There is no such thing known as "visible goods" and "invisible goods".
We come across only "visible trade" and "invisible trade": "Exchange of physically tangible goods between countries, involving the export, import, and re-export of goods (such as coal or crude oil) at various stages of production. It is distinguished from invisible trade, which involves the export and import of physically intangible items such as services( eg.freight and passenger transport, intellectual property and patents)."
visible trade = 有形贸易=有形商品交易;
Invisible trade=无形贸易="服务"交易.

Answer 2

怎么辨别有形和无形的商品？追问

用英文回答