如果原句是There is no guarantee that a business will always be in a position to pay its debts.那么Imissyou2smile这个人解释的是对的.是同位语从句.
下面我帮你区分一下同位语从句和主语从句.
1. 同位语从句： 主要由连接词that引导,用来说明先行词的具体内容,与先行词是同位关系. 简单记法, 由that引导,解释that 前面那个名词的.当然有时也由where,who, whether 指导,但不常见.
例子：The truth that the earth moves around the sun is known to all.
the truth 作为主语, that the earth moves around the sun 作为truth同位语,解释说明是怎样的一个真理.
2. 主语从句.主语从句在复合句中作主语的主语.简单来说：情况有以下几种
A. 就是that+一个完整句子（陈述句）+谓语（is. am,are,.)+宾语.
That the earth moves around the sun is known to all
B.when, who,where, how 等连接词组成的一个句子（疑问句）+谓语（is. am,are,.)+宾语.
Who will go is not important.
When he will leave for Beijing is not decided yet.
主语从句简单来说,就是前面一个完整句子+谓语（is. am. are)+宾语.
当然还有这种情况：
由it 作为形式主语代表主语从句,
It is a pity that she has made such a foolish mistake.
建议买那本『高中英语语法大全』修订版,真的好有用.我那本书高中买的,五年了.不知现在能否买的到.