cf.) shuffle from foot to foot
（＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿＿）
cf.)shift one's weight from foot to foot
（＿＿＿＿＿＿＿＿＿＿＿＿＿＿）
Optimized studying based on the forgetting curve vastly improves memorization. - What is reminDO?
Memorize
