Think of a coin lying on the table with a number printed on its front. You read the number and you stop there: that is what the coin says about itself. What someone would actually give you for it is a different question, and the whole word exists because those two numbers can drift apart. Take that habit of reading only the front and turn it on a person's words, and you have the other meaning.
One branch
只讀正面寫的那個數字
一個是真的在看硬幣的正面，一個是把同樣的動作用在別人的話上。兩邊都在說：我只取它表面給我的那個值，不往後面看。
noun · B2
The value printed on the front of something such as a coin, a stamp, a ticket or a bond — the amount it says it is worth, which may not be the amount people will actually pay for it.
面額