He is five years senior to me.

你对这个句子的理解是错误的。本句并不是senior to me修饰five years. 而是相反，five years 修饰senior。

He is senior to me. = He is older than me. 他比我年龄大。senior是源自拉丁语的形容词，在拉丁语中是比较级, 比...年长/职位高等。如果需要表示年龄大多少，则可以用名词词组或副词修饰比较级，表示程度。

He is five years senior to me.= He is five years older than me.

表语是以形容词为中心词的形容词词组。

It is the phone expensive to me.

She is the girl beautiful to me.

由于你的上句结构的理解错误，导致你模仿该结构造出的这个二个句子都是错句。