180. He is by no means a smart boy.
→He is not 

179. His appearance was completely unexpected.
→His appearance 

178. The riddle of the missing heiress has been solved.
→The police 

177. Gunman kills 3 people in Bank Drama.
→A man 

176. Amanda has improved a lot this term. (PROGRESS)

175. Come on Thursday or Friday. It’s all the same to me.
(DIFFERENCE)

174. I know you are hiding something from me. (BACK)

173. We’ve decided to leave early tomorrow morning. (SET)

=172. We have an emergency electricity supply in case we are cut
off. (BACK)

171. Interrupting when someone is speaking is rude. (CUT)