【简答题】阅读理解。 When a cat is frightened, its heart starts beating faster, its muscles (肌肉) get tense, and there are changes in the chemicals in its blood-stream. If the er continues, it will defend itself,...
【单选题】Switzerland lies at the heart of Europe. To its west is France, to the north is Germany, to the east lies Austria and to the south, Italy. All of these countries have had an influence on Switzerland' ...