① We cannot know everybody whom it would be to our benefit to know, because there are too many of them.

② I believe there are a number of questions that it is no use our asking, because they can never be answered.

③ Beauty is a letter of recommendation which it is almost impossible to ignore.

④ The masses are likely to replace an unchanging mode of life by fashion which it will be in the economic interest of certain people to change as often as possible.