時間・時点N2
〜ごとに
every... / each time...
Structure
N + ごとに；V-辞書形 + ごとに；数量詞 + ごとに
Explanation
Means "every...". Three uses: ① after time nouns (一時間ごと) "every X hours"; ② after the dictionary form of verbs (会うごとに) "each time one does X"; ③ after counters in proportions (10人ごとに1人). Also used as 〜ごとのN.
Examples
彼女は会うごとに、きれいになっていく。
She gets more beautiful every time I see her.
この薬は8時間ごとに飲んでください。
Take this medicine every eight hours.
Note
〜おきに ("at intervals of") is close in meaning; however it cannot express "every time one does X" like ごとに can.
Related Grammar
〜おきに〜たびに