She stepped on my foot _______, not _______, which made me angry.
158. It is said in the book that Thomas Edison _____ the world leading inventor for about sixty years.
159. The wages ______ him will be paid tomorrow.
160. I don’t really work here; I ______ until the new secretary arrives.
161. As I was about to speak ______ you interrupted me.
162. Many countries are increasing their use of natural gas, wind and other forms of ______.