----Mum, it’s so hot and I am very thirty. ---- Here’s the money, Tom. Go and buy _____ an ice ream.
The maths problems are too hard, only ______ people can work them out.
---______ does he go to Guangzhou on business? ---Three or four times a year.
I always go to the lake ____ the aftenoon, but Kate goes there ____ the night of Monday.
Jack _______ goes shopping, because he is ______ busy working.
Helen is my cousin. I often help ________ with ________ homework.