I met him this day last week, that is, the 25th of June

Around his facts the scientist weaves a logical pattern or theory which gives the facts meaning, order, and significance

Credit is the amount or sum placed at a person's disposal by a bank; a loan of money

Foreign trade consists of a two-way flow of commodities-export and import

I'll pay you back a week from today, that is, on July 21

That is to say, a language is something that we learn and are taught, not something that we know by instinct