十七seventeen通常总共只有十一二个会员。

现在将至少有十七个。Normally it has only had eleven or twelve members in all. Now it will have seventeenat the very least. 最早提及炸药的是十七世纪上半叶炼金术的著作。The earliest mention of explosives are to be found in the alchemical writings of thefirst half of the seventeenth century.