as needed
US /æz ˈniːdɪd/
UK /æz ˈniːdɪd/

1.
khi cần, tùy theo nhu cầu
when or where necessary; as required.
:
•
Add water as needed to the mixture.
Thêm nước khi cần vào hỗn hợp.
•
The nurse will change the dressing as needed.
Y tá sẽ thay băng khi cần.