China's population is expected to increase to about 1.5 billion in 2040, ______it will start to decline slowly.
It_________ to me that I should pay a visit to my friend Jane.
There was no_________ about it that they had got the news.
It was soup _________ Oliver was eating.
He told me he had been offered a very well-paid_________ abroad.
When_________why he was late, he made no answer.