jìn / xíng / mā / zhǎn / jiāo / yì / qián / tóu / zī / zhě / bì / xū / liǎo / jiě / zhuī / jiā / bǎo / zhèng / jīn / de / fēng / xiǎn进行孖展交易前,投资者必须了解追加保证金的风险。Before trading on margin, investors must understand the risk of margin calls.