请你写出一个至少有加数为正整数且和为-6的算式（ ）
3+（-7）+（-2）=-6（答案不唯一）
His sunburnt face is just like that of millions of Chinese farmers, whom he has struggled the past five decades.
A．to; for
B．for; to
C．for; for
D．with; for
内毒素的毒性成分是（）。
