keep one's eye on ( or take one's eye off) the ball
keep (or fail to keep) one's attention focused on the matter in hand.
→ ball
keep one's eye on ( or take one's eye off) the ball
keep (or fail to keep) one's attention focused on the matter in hand.
→ ball
Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004