Whose eyes did this come through?
Japanese is fussy about marking how you know. Five overlapping endings cover 'it seems / I hear / it looks like': 〜ようだ (objective inference: 'it appears, judging by what I see / read'), 〜みたい (the colloquial twin of 〜ようだ), 〜らしい ('I gather / apparently' — secondhand info, or 'typical of'), 〜そうだ plain-form attached (HEARSAY — 'I hear that ~'), and 〜そうだ stem-attached (APPEARANCE — 'looks like / about to ~'). The two 〜そうだs look identical but attach differently and mean very different things — that's the central trap of this lesson. Roughly: ようだ / みたい = my own inference. らしい = I got it from somewhere / it's the typical version. 〜そうだ (plain) = I heard it. 〜そう (stem) = it looks that way to me right now.
〜ようだ — 'it appears / it seems' (your own inference)
〜ようだ says 'based on what I'm seeing / hearing / reading, it appears that ~'. It's your own conclusion from evidence. Attachment: plain forms attach directly, but な-adjectives take 〜な ようだ and nouns take 〜の ようだ. だれか いる ようだ。 = 'It seems someone is there.' 山田 さん は つかれて いる ようです。 = 'Mr. Yamada appears to be tired.' この みせ は 高い ようです。 = 'This shop seems expensive.' しずか な ようです。 = 'It seems quiet.' 学生 の ようです。 = 'It appears (he) is a student.' 〜ようだ has a slightly written / careful feel — at home in essays, news, polite speech. It also doubles as 'like ~ / similar to ~' with の よう に (ゆめ の よう に きれい = 'pretty like a dream') but that's a separate use.
〜みたい — colloquial 〜ようだ
〜みたい is 〜ようだ's spoken-Japanese twin. Same meaning, casual register. Attachment is simpler: it goes after a noun, na-adjective stem, or plain verb / i-adj with no な or の in between. だれか いる みたい。 = 'Seems like someone's there.' 山田 さん は つかれて いる みたい です。 = 'Mr. Yamada seems tired.' しずか みたい。 = 'Seems quiet.' 学生 みたい。 = 'Looks like a student / seems to be a student.' みたい also conjugates like a な-adjective: みたい な + noun (ゆめ みたい な 話 = 'a dream-like story'), みたい に + verb (子ども みたい に わらう = 'laugh like a child'). In conversation, みたい is far more common than ようだ.
〜らしい — 'I gather / apparently / typical of'
〜らしい has two related uses: (1) secondhand information — 'apparently / I gather that ~ (from talk, news, what people say)'. 山田 さん は あした 来ない らしい です。 = 'Apparently Mr. Yamada isn't coming tomorrow.' Compared to 〜ようだ (your own inference) and 〜そうだ plain (a specific report you heard), 〜らしい is more diffuse — 'word on the street is...'. (2) 'typical of / characteristic of' when attached to a noun: 男 らしい = 'manly / like a real man'; 春 らしい 日 = 'a really spring-like day'. Distinguish by attachment: 学生 らしい です could be 'apparently a student' OR 'student-like / typical of a student' — context decides. Attachment: plain forms direct; nouns / na-adj stems direct (しずか らしい, 学生 らしい).
〜そうだ — HEARSAY ('I hear that ~')
Plain form (verb / i-adj / na-adj だ / noun だ) + そう だ / そう です. This says 'I heard / it's said that ~'. Source is often added with 〜に よる と ('according to'). 天気 よほう に よる と、あした は 雨 が ふる そう です。 = 'According to the weather forecast, it'll rain tomorrow.' 山田 さん は 来週、けっこん する そう です。 = 'I hear Mr. Yamada is getting married next week.' この 本 は おもしろい そう です。 = 'They say this book is interesting.' しずか だ そう です。 = 'I hear it's quiet.' Hearsay 〜そうだ has no past-tense form of itself — you put the past on the inner verb: 来た そう です = 'I hear (he) came'. It also doesn't conjugate: there's no 〜そうじゃ ない, no 〜そう だった. To negate, you negate the inner statement (来ない そう です = 'I hear (he) isn't coming').
〜そう — APPEARANCE ('looks like / about to')
Verb stem (or i-adj stem, or na-adj stem) + そう. This says 'it looks like ~ / it seems ~ (right now, by my eyes)'. Verb stem = the ます-form minus ます: ふる → ふり → ふり そう. 雨 が ふり そう です。 = 'It looks like it's about to rain.' おちそう！ = '(That's) about to fall!' おいし そう！ = 'Looks delicious!' (drop the final い of おいしい). しずか そう = 'looks quiet'. 元気 そう です ね。 = 'You look well!' Two irregularities: いい → よさ そう ('looks good'), ない → なさ そう ('doesn't seem to be / looks like there isn't any'). This 〜そう conjugates like a な-adjective: おいし そう な ケーキ ('a delicious-looking cake'), おいし そう に 食べる ('eat with apparent enjoyment'). It carries an immediate, visual feel — hearsay 〜そうだ is about reports; appearance 〜そう is about right-now-with-my-eyes.
Telling the two 〜そうだ apart — by attachment
This is the big one. Same ending, different attachment, different meaning. Hearsay = plain form + そうだ: ふる そう です ('I hear it'll rain'). Appearance = stem + そう: ふり そう です ('it looks like it'll rain'). For i-adjectives: hearsay おいしい そう です ('I hear it's delicious'); appearance おいし そう です ('it looks delicious' — the い is dropped). For nouns and na-adjectives, hearsay uses だ そう です but appearance basically can't attach to nouns at all (you'd say 学生 みたい / 学生 の よう instead). Quick test: if you can paraphrase as 'I heard from someone that...', it's hearsay (plain + そう). If you can paraphrase as 'just looking at it, I'd say...', it's appearance (stem + そう).
