The potential of economic development of one region varies from ______ of another.

How can I help ________ if people just don’t follow my advice?

There is ______ wrong with this computer. It doesn’t work well.

—What about asking these new graduates to take on the task?—I m afraid not．While they are energetic and ambitious, _____ of them seems to be suitable for this demanding job．

Now old Henry is very sad, so he doesn't want to do         .