get up to
US /ɡet ʌp tuː/
UK /ɡet ʌp tuː/

1.
замышлять, делать
to be busy with something, especially something that other people might not approve of
:
•
What have you been getting up to?
Что ты замышлял?
•
The children are always getting up to mischief.
Дети всегда проказничают.