阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

Among the capitals of big economies, Beijing enjoys a surprising distinction. 【小题1】 its sometimes unpleasant weather, it hosts more species of birds than any other such city apart from Brasilia. Remarkably, however, birdwatching remains 【小题2】 (common).

In many countries, birders play an important role in 【小题3】 (spot) changes in bird populations and behaviour. A British enthusiast in Beijing Terry Townshend, has recently set up 【小题4】 means of doing so without needing to stand for hours outdoors. It involves a digital listening device 【小题5】 (fix) on the roof of a 15-storey building in northern Beijing. For several months until mid-November it recorded the night-time calls of migratory birds flying above. The sounds will be used to identify night-lying species, some of 【小题6】 are not commonly seen overhead by day. The technique has been used in America and Europe, but Mr Townshend thinks this is its first known 【小题7】 (apply) in Asia. Such devotion is rare among 【小题8】 (amateur).

China has little history of birdwatching. Only in the 19th century did the scientific study of birds begin. Birdwatching as a pastime 【小题9】 (emerge) only in the past two decades, helped by rising incomes that have allowed people to buy binoculars and cameras. There is a small but growing number of local birders who 【小题10】 (close) monitor bird migration and draw public attention to human threats to birds.