Русско-английский словарь пословиц и поговорок
ЗА ВСЕ БРАТЬСЯ НИЧЕГО НЕ УМЕТЬ
A person who follows many diverse occupations is never competent in any
Cf:Не teaches ill, who teaches all (Am.). Не that sips many arts drinks none (Am.). Jack of all trades is master of none (Am.,Br.). A man of many trades begs his bread on Sunday (Am.)