名詞 folder:

1. a small book usually having a paper cover
   同義詞：booklet, brochure, leaflet, pamphlet
2. covering that is folded over to protect the contents

1. The folder was sandwiched in between the two bulging files in the drawer.
   這硬紙卡被擠在抽屜里的兩個(gè)鼓鼓的檔案夾里了。
2. God, we look like sheep- we are all carrying the same folder.
   天啊！我們都帶著同樣的文件夾，看起來(lái)一模一樣。
3. A container, such as a cabinet or folder, for keeping papers in order.
   文件夾按順序放置文件的容器，如檔案柜或文件夾

fold.er

n.（名詞）
One that folds or is folded, such as a booklet or pamphlet made of one or more folded sheets of paper.
折疊者，折疊器，折疊印刷品：折疊或被折疊起來(lái)的東西，比如由一張或多張折疊起來(lái)的紙制成的小本子或小冊(cè)子
A flexible cover folded in the center and used as a holder for loose paper:
文件頭，紙夾：一個(gè)中間折起的可彎曲封皮，用作夾放散紙的紙夾：
例句：
a file folder; a hanging folder.
文件夾；懸掛的文件夾