Where the words come from
The definitions of the balance of trade and the current account balance, the four components of the current account, the link between a deficit and an inflow of financial capital, and when a deficit is harmful — Principles of Economics 2e, OpenStax, licensed CC BY 4.0. https://openstax.org/books/principles-economics-2e/pages/23-1-measuring-trade-balances and https://openstax.org/books/principles-economics-2e/pages/23-3-trade-balances-and-flows-of-financial-capital and https://openstax.org/books/principles-economics-2e/pages/23-5-the-pros-and-cons-of-trade-deficits-and-surpluses. Changes: The United States current account table and Work It Out replaced with an invented UK quarter; the four components given their UK names, "merchandise" as trade in goods, "income payments" as primary income (the primary income card is our wording, widened to the UK definition, which also counts compensation of employees) and "unilateral transfers" as secondary income; the card examples invented or adapted from the section's own cases; the Robinson Crusoe parable and the United States, South Korea, Latin American, East Asian and Japanese cases reduced to their conclusions; "trade deficit" read as the current account deficit, as the source does; British spelling; "trucks" to "lorries"; 29 September: the card examples shortened; the capital and financial accounts explain and its check are our own words.
The question and the page layout are our own.