Let T2 be future period T1 be the option period .if the option period and futures period are the same,then Fe*-rT2=Se*-δT1,but  if T2>T1,then F=Se*(r-δ)Τ2,谁知道为啥啊？F是future价格，S是股票价格，r是无风险利率，δ是连续股票利率。谁知道告诉我啊！谢谢