同学,才看到你向我们团队发来的求助题,现在为你解答
翻译：We will hold a science lecture from 8:00 to 10:00 on next Saturday morning.
或用被动语态表达：
There is going to be a science lecture held by us from 8:00 to 10:00 on next Saturday morning.
解析：科学报告会可以直接表达为science lecture,主动和被动都可以表达.
翻译：我们将举办一次科学报告会在下周六上午8:00-10:00.
有不明白的请继续追问,