Must be replaced by cash means that the ETF constituent stocks must be replaced with cash when subscribing and redeeming due to suspension of trading, related stocks, etc. \x0d\ That is, stocks cannot be used when subscribing or redeeming. If the stock is not returned, it will be in cash. \x0d\There are "must", "allowed" and "prohibited" cash substitution ETFs, and some of their constituent stocks are securities and some are cash. \x0d\ \x0d\ "Refund" cash substitution means that investors can only use cash to apply for redemption, and cannot use component securities, such as gold ETFs. \x0d\ \x0d\Every ETF application and redemption will have a secondary liquidation in which more cash will be refunded and less money will be replenished.