请根据句意从方框中选择合适的动词，并用其适当时态填空，使句子通顺。

The water in the river _________dirtier if nothing is done.
When I visited her last night, she __________by the fire and thinking.
My father _________to Beijing for his business last night.
I’m a singer is the most popular programme that I           so far.
The geography teacher told us that Diaoyu Island ___________ in the east of China.