.Their are in the bookcase.
—How will you deal with these papers, Ann? —I will leave them to ________ takes over the job.
—What upsets him? —________ his computer is out of order.
Whether ways will be found to stop pullution or not is just ________ worries the public.
I would appreciate ________ you could give me some advice on learning English.
The local Tibetans and Sherpas laughed at the strange bottles containing ________ they referred to as “English air”.