The suffix 〜がち is attached to nouns and verb stems to express that something has a tendency to happen or that someone is prone to a certain state. It translates naturally to “tend to,” “apt to,” or “prone to.”
Crucially for JLPT students, this grammar point is almost exclusively used to describe negative tendencies or undesirable states (e.g., being late, getting sick, forgetting things, or cloudy weather). It sounds highly unnatural to use it for positive habits.
Formation and Rules
【Verb Stem】+ がち (e.g., 休む ➔ 休みがち / Prone to taking time off)
【Noun】+ がち (e.g., 病気 ➔ 病気がち / Prone to illness)
Common Verb Usages
You will frequently see がち attached to the verb 有る (to exist/happen) in the form of ありがち, which means something is a common occurrence or a typical trap people fall into.
ありがちな考え方。
A typical way of thinking.
ありがちな誤解。
A common misconception.
それは初心者にありがちなミスだ。
That is a mistake common among beginners.
メンバーが大勢いると結論のない議論になりがちである。
When there are many members, discussions tend to end up without a conclusion.
疲れているときは、ミスを犯しがちだ。
When you are tired, you are prone to making mistakes.
Common Noun Usages
When attaching to nouns, がち is usually limited to a handful of specific words, mostly related to health, personality, or weather patterns.
最近、母は病気がちです。
Lately, my mother has been prone to illness.
今週は曇りがちの天気が続くでしょう。
This week, cloudy weather is likely to continue.
Modifying Other Nouns (〜がちな)
Because がち acts grammatically like a な-adjective, when you use it to modify another noun directly in the middle of a sentence, you must attach な (and occasionally の) to it.
遠慮がちな態度。
A reserved (hesitant) attitude.
留守がちな家。
A house that is frequently empty (the occupants tend to be away).