I am doing without sugar in my coffee.

She is doing down the stairs.

He is doing the Dutch by refusing to pay his share of the bill.

I am doing lunch with my colleagues today.

She is doing by halves and not putting in her full effort.

They are doing battle against their enemies.

She is doing well in her new job.

She is doing a Melba in the kitchen.

His ill-doings have caused a lot of harm.

During the square dance, they performed a do-si-do.