题目

阅读下面材料，在空白处填入适当的内容（1 个单词）或括号内单词的正确形式。 Every autumn, millions of the North American monarch butterflies manage (travel) around 4, 000 kilometres south and find their way to places they will spend the winter. A team of scientists (lead) by Professor Eli Schlizerman at the University of Washington has discovered that the monarch is able to tell the time of the day and then uses (it) eyes to measure the position of the sun. These two (piece) of information allow the butterfly to determine which way it needs to go. The monarch's population (crash) by as much as 90 per cent in the last few years. (sad), human activity is the main reason why number of the North American monarch butterflies is falling.  The research on the monarch's behaviour has however led a greater awareness of this creature. The more we know about this lovely creature, the (great) the chance it will survive. 答案：【1】to travel【2】where【3】led【4】its【5】pieces【6】has crashed【7】Sadly【8】the【9】to【10】greater

查看本题答案和解析