Complete the sentences using the present perfect or the present perfect continuous.
they ____ a cake for your birthday. (buy)
she ___her weekend for the last two days. (plan)
My mum ____ dinner for two hours. ( cook)
You ____ all day! (pack)
I ____ Jennifer for ten years. (know)

They have bought a cake for your birthday.
— Present perfect: действие уже завершено, торт уже куплен.

She has been planning her weekend for the last two days.
— Present perfect continuous: процесс планирования длится уже два дня.

My mum has been cooking dinner for two hours.
— Present perfect continuous: приготовление началось раньше и продолжается сейчас.

You have been packing all day!
— Present perfect continuous: вы занимаетесь сбором вещей весь день.

I have known Jennifer for ten years.
— Present perfect: глагол know обычно не используется в continuous, поэтому нужен present perfect simple.