。
She talks just like a teacher.
Literal
[topic-は] just-like teacher [genitive-の][as-ように] speaks.
まるで~のように layers two structures: まるで ('exactly like') + Nのように ('in the manner of N'). Pairing the simile setup with the verb 話す ('speak') gives 'speaks in the manner of [a teacher].' Slightly evaluative — the sentence implies that her speech has the patterned, didactic, perhaps lecturing quality of a teacher (often slightly tongue-in-cheek). The polite ~ます ending makes this a public observation rather than a private aside. Note: 先生 in Japanese addresses not only teachers but also doctors, lawyers, politicians, and writers — anyone in a position of expertise.