custom or customs

English as a Second Language English Vocabulary, Grammar and Idioms
1

hey,i was wondering the difference between custom and customs.
normally,we use [american customs],but is it ok if we say[american custom],cuz by looking up the dictionary,i found that both words could be used to refer to[custom/customs].

otherwise,when using [customs],is it a singular or plural subjecive?

thanks in advance for the help!

2

Use the plural when you are speaking about the duties, the office, and the airport facilities. Here is what Dictionary.com has to say:

customs
a. ( used with a singular or plural verb ) duties imposed by law on imported or, less commonly, exported goods.
b. ( used with a singular verb ) the government department that collects these duties.
c. ( used with a singular verb ) the section of an airport, station, etc., where baggage is checked for contraband and for goods subject to duty.

3

thanks for such a quick reply!
and it should be like…[ american customs are…].right?

but when do we use the singular form?

thanks again!

4

What kind of customs are you talking about, fees for imported goods or traditional cultural habits?

5

got it,for departments in charge of importing/exporting goods,always keep using [customs] and keep the subjective pluralized
right?

6

And use the singular verb as the definitions above clearly indicate.