假如你是Mike，你的朋友Susan近来心情不好，请你给她发一封E-mail，提出合理性的建议，帮助她调适心情。

字数：80—100字（首尾句已给出，不记入所要求的总字数）。

供你参考的建议有：

sing, take a walk, do sports, write the diary, watch TV, listen to music, go shopping, go swimming, go outside…

Dear Susan,

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Yours

Mike

简述两栖动物从水生过渡到陆生所要面临的问题。