I was going to take a photo of the world-famous painting when I noticed a__________ saying “No Photographing”.

The medicine bought at a high price turned out to have no _____. 

There might be life on other planets, but so far scientists haven’t found enough _____ to prove it.

Achieving a high degree of proficiency in English as a foreign language is not a mysterious _____  without scientific basis.

As we all know, the Internet will let people have ____  to huge amounts of information from their own homes.