Closing a position means selling long positions and buying short positions. Short position means that the funds can't make up for the loss, and the brokerage firm forcibly liquidates the position, that is, the loss exceeds the principal, but the general bookmaker will not really lose to a negative number, and will set a ratio for this loss, which will be stronger when the principal is still 20-30% (for example only). Leverage is a transaction of borrowing money (50,000 after owning100,000) or borrowing money (selling debt first without holding positions). Take profit and stop loss is to artificially set a trading price (how much you earn and how much you lose), and when you reach this price, you will make a deal, regardless of the market outlook.