まさに蛙の面に水とはこのことだろう。

Sentence Analyzer

まさに この こと だろう

English Translation

That's a clear case of "water off a duck's back".

Furigana

まさに(かえる)(めん)(みず)とはこのことだろう。

Romanji

Masani kaeru no men ni mizu to wa kono koto darou.

Words

正に (まさに)
exactly; surely; certainly; just (about to); on the verge (of doing or happening); duly; naturally
(かえる、かわず、かいる、カエル、カワズ)
frog; kajika frog (Buergeria buergeri)
()
indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question
(めん)
face; mask; face guard; (in kendo) striking the head; surface (esp. a geometrical surface); page; aspect; facet; side; chamfer; counter for broad, flat objects, levels or stages, e.g. in a video game
()
at (place, time); in; on; during; to (direction, state); toward; into; for (purpose); because of (reason); for; with; by; from; as (i.e. in the role of); per; in; for; a (e.g. "once a month"); and; in addition to; if; although
(みず、み)
water (esp. cool, fresh water, e.g. drinking water); fluid (esp. in an animal tissue); liquid; flood; floodwaters; water offered to wrestlers just prior to a bout; break granted to wrestlers engaged in a prolonged bout
()
if; when; and; with; particle used for quoting (with speech, thoughts, etc.); quoting particle; promoted pawn; indicates question (sentence end)
()
topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis
此の (この)
this (something or someone close to the speaker (including the speaker), or ideas expressed by the speaker)
(こと、こん)
thing; matter; incident; occurrence; event; something serious; trouble; crisis; circumstances; situation; state of affairs; work; business; affair; after an inflectable word, creates a noun phrase indicating something the speaker does not feel close to; nominalizing suffix; pretending to ...; playing make-believe ...; alias; aka; nickname; alternative name; also known as
()
be; is; indicates past or completed action; indicates light imperative

Kanji

Readings: ア、 ワ、 かえる、 かわず
Meaning: frog
Readings: メン、 ベン、 おも、 おもて、 つら
Meanings: mask, face, features, surface
Readings: スイ、 みず、 みず-
Meaning: water