The research is so designed that once _______ nothing can be done to change it.
103. Can you _____ the difference _____ American English and British English?
102. In the minority nationality the custom doesn’t ____ and has come down from generation to generation.
101. Many English teachers like to _____ dictation _____ their students.
100. My cousin wants to be a scientist and _____ science of nuclear.
99. China is the biggest _____ country, while the U.S.A is the biggest ____ country.