～がたい
hard to do, literary
～がたい attaches to the ます-stem of a verb and creates an い-adjective meaning the action is so difficult it is nearly impossible: 信じます becomes 信じがたい, “hard to believe”. It belongs to written and formal Japanese.
Unlike ～にくい, which marks a practical difficulty with almost any verb, ～がたい combines with a narrow set of verbs of belief, understanding, and acceptance — 信じる, 理解する, 許す, 受け入れる, 忘れる — and the obstacle is psychological, not physical. It maps to English turns like “scarcely believable” or “hard to accept”.
1. Nearly impossible to believe or accept
The core use: the speaker cannot bring themselves to believe, forgive, or accept something.
彼の話は信じがたい。
“His story is hard to believe.”
- 彼（かれ）= he
- の = possessive marker
- 話（はなし）= story
- は = topic marker
- 信じがたい（しんじがたい）= hard to believe, scarcely believable
2. Set, almost lexicalized combinations
Several ～がたい forms function as fixed vocabulary, often directly before a noun. 忘れがたい (“unforgettable”) and 動かしがたい事実 (“an indisputable fact”) are typical.
あの夏の出来事は忘れがたい思い出になった。
“The events of that summer became an unforgettable memory.”
- あの = that
- 夏（なつ）= summer
- の = links the two nouns (of)
- 出来事（できごと）= events, happenings
- は = topic marker
- 忘れがたい（わすれがたい）= unforgettable
- 思い出（おもいで）= memory
- に = marks the result of the change (into)
- なった = became (past of なる)
How to form it
Verb ます-stem + がたい (conjugates like an い-adjective)
- 信じる（しんじる）= to believe → 信じがたい（しんじがたい）= hard to believe
- 許す（ゆるす）= to forgive → 許しがたい（ゆるしがたい）= unforgivable
- 受け入れる（うけいれる）= to accept → 受け入れがたい（うけいれがたい）= hard to accept
Key idea
～がたい says the speaker cannot bring themselves to do something, in a formal, written style. If a pen is simply awkward to write with, that is 書きにくい; if an insult is beyond forgiveness, that is 許しがたい.
Other N1 grammar
Updated .