China’s population is expected to increase to about 1.5 billion in 2040, _____ it will start to decline slowly.
I asked him whether he had done all the work himself ________ whether he had had any assistance.
I was on the point of going to bed ________ Mr. Zhang rang.
English is understood all over the world ________ Turkey is spoken by only a few people outside Turkey itself.
In this factory, it's hard to tell cadres ____ workers.
My brother is very good ___ ping-pong.