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Learn a little bit every day.
Literal
Every-day little-by-little learn [command-なさい].
少しずつ ('little by little') uses the suffix ~ずつ, which distributes a quantity evenly — 'a little at a time.' Commonly attaches to quantity words: 一つずつ ('one at a time'), 少しずつ ('a bit at a time'). A nice piece of teacher or parent advice.