When I passed the river, I saw some children ______ on the sand.

They have T-shirts _______ green and black for only $13 _______ the shop. [ ]

Yesterday Tony bought a scooter ______ 150 yuan.[ ]

I have to buy _________of the two books because I don’t know which to choose.

The great millionaire gave away all his fortune to the charity and lived a simple life，________.