～がい
worth doing
～がい attaches to the ます-stem of a verb and creates a noun meaning the worth or reward of doing that action: やります becomes やりがい, “the sense that the work is worth doing”.
English has no single equivalent; sentences with ～がいがある usually translate as “rewarding” or “worth doing”. Note that unlike ～にくい, which builds an adjective, ～がい builds a noun, so it takes particles like が and の.
1. ～がいがある / ～がいがない
The most common frame: say the activity has (or lacks) reward value with がある or がない.
この仕事はやりがいがある。
“This job is fulfilling.”
- この = this
- 仕事（しごと）= job, work
- は = topic marker
- やりがい = the worth of doing it, sense of fulfillment
- が = subject marker
- ある = there is, to have
2. As an independent noun
Some ～がい words are everyday vocabulary in their own right. The most famous is 生きがい, “what makes life worth living”.
孫の成長が彼女の生きがいだ。
“Her grandchild's growth is what makes her life worth living.”
- 孫（まご）= grandchild
- の = possessive marker
- 成長（せいちょう）= growth
- が = subject marker
- 彼女（かのじょ）= she
- 生きがい（いきがい）= reason for living
- だ = copula (is)
How to form it
Verb ます-stem + がい (the result is a noun)
- やる = to do → やりがい = the worth of doing it
- 生きる（いきる）= to live → 生きがい（いきがい）= reason for living
- 働く（はたらく）= to work → 働きがい（はたらきがい）= the reward of working
Key idea
～がい names the payoff your effort earns. If doing something gives you a sense that the effort was worthwhile, the activity has ～がい; if the effort feels wasted, it is ～がいがない.
Other N2 grammar
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