play into someone's hands
US /pleɪ ˈɪntu ˈsʌmwʌnz hændz/
UK /pleɪ ˈɪntu ˈsʌmwʌnz hændz/

1.
لعب في يد شخص, خدم مصلحة شخص
to do exactly what your opponent wants you to do, so that they gain an advantage over you
:
•
By arguing with him, you're just playing into his hands.
بمجرد الجدال معه، أنت فقط تلعب في يديه.
•
The opposition's mistakes played right into the government's hands.
أخطاء المعارضة لعبت مباشرة في أيدي الحكومة.