The order of answers is as follows:

1. In this context, there is no need to translate it, because it is English and cannot be too Chinese. Adding this parenthesis is more British and is influenced by Cultural impact!

2. OEM is a proper noun, the English abbreviation is OEM, in the sentence it means make things that are sold under others' brands.

3. Offline sales, that is Refers to products generally sold below the company's price control line!

Hope you adopt it! ! !