I have two uncle, but ____ of them lives here.

--It snowed heavily last night. Is ______here today?---Yes,and ______of us was late for school this morning.

 ______ is necessary for everyone to obey the traffic rules.

In his lecture, the professor referred to the belief, in contrast to all other countries, _____ the elderly are wise, _____ is particularly dominant(占优势的) in the Chinese culture．

There were many people standing by, but _____ of them were willing to help the poor boy.