Shirabe
二つ ずつ

宛ずつ

Common suffix
English jmdict
1
suffix word usually written using kana alone apiece;each
１つ１つの出願を１件ずつ考慮しなければならないだろう。
We will have to consider each application on a case-by-case basis.
2
suffix word usually written using kana alone at a time;piecemeal
その一節を一語ずつ訳しなさい。
Translate the passage word for word.

二つずつふたつずつ

Adverb Noun Noun
English jmdict
1
adverb (fukushi)nouns which may take the genitive case particle 'no'noun (common) (futsuumeishi) two at a time;two by two;in twos
Other forms 二つづつ 【ふたつずつ】 · 二つ宛 【ふたつずつ】 (search-only kanji form)