阅读短文，从方框中选出适当的单词填空

Dear Ricky,
    How are you ____ on? Thanks very much for sending me the pictures and the English reading materials. From the pictures I can ____ that your school looks very beautiful. The reading materials are very useful and ____. I can learn a lot from them.  Some stories are so interesting that I like them very much.
    Now I don't have ____  time for my hobbies. I am busy getting ready for the coming exams. I’m working hard at all my lessons because I want ____ a better result.
    I'm looking forward to hearing from you soon.
Yours,
Wu Ming

如果双曲线y=$\frac{m}{x}$经过点（2，﹣1），那么m=____ ．

读《悬岩边的树》，结合“孤单”“寂寞”“倾听”等词语，说说“悬岩边的树”有何象征意义？

下面关于重力说法中正确的是（ ）