区别：last/remain表持续；recycling/recycled material表可回收金属
原句分别是：
"the sweets could [last] through the year!”i thought,and they did.
the stuff used to be thrown about ,but now it is [recycling] material.
注：中括号内为正确答案,请说明两者不同和为什么在这里不用另外一个?