something 和anything 都是不定代词。something 意为某事，用于肯定句中；anything 意为任何事情，用于否定句或疑问句中，根据形容词修饰不定代词要后置的原则，故选B.例句迟些再补。
raise 提高
collect 收集
lend 借给
borrow借入
social 社会的
volunteer 志愿者
fill 填满
improvement 改善
be covered 被……覆盖
I know many children can't go to school. because they aren't able to afford* it.
That's true* let's raise money to help them.
