Linear operator
线性算子，线性运算器
🧩 词语组成解析
🗣️ 情景例句
who spent the last five years
用过去五年的时间
He is truly happy who makes others happy.
真正幸福的是使人幸福的人。
The vicar has been asked to have the tree cut down, but so far he has refused.
人们曾请求教区的牧师叫人把树砍掉，但他直到现在也没有同意。