He was very rude to the Customs officer, _____ of course made things even worse.
250. Every year Harvard University awards to excellent foreign students in theoretical physics.
249. A_____ has taught us what atoms are made up of and how powerful the atom bomb is.
248. A group of the red scarves are playing on the seaside_______.
247. He found it quite impossible to learn _____ well in less than 6 months so he registered for the next semester(term).
246. Nelson Mandela played and is still playing a leading ________ in ending apartheid(种族隔离政策) in South Africa.