根据下面每段话的陈述内容，从方框中选出各段恰当的主题句，并将其字母序号填入题后的横线上。

1．Mr. and Mrs. Roper had a clever bird．Their son，Robert，often travelled a lot in his work．The bird always started calling “Robbie” a few hours before Robert appeared at the door．______

2．My friend and I had a picnic in a quiet place and played some Mozart on a CD player．Later, we were amazed to find some cows listening to the music carefully around us．______

3．In France, a man with his dog had to move to a new job 200 kilometers away．He left his cat at his old house．About three weeks later, the dog went away．Then seven weeks later, the dog and the cat came back together．They were tired and  hungry after their long travel．_______

4．A friend was moving to another country, so we took his pet goldfish back and put it in a bowl with our goldfish．After six months, my friend came back and took it home．The next day both his goldfish and mine died．I believed the departure （分离）broke their hearts．_____

5．Bill Bowell always felt sad．His friend told him to swim with a dolphin．He made friends with a dolphin called Simo．Then his life changed．Simo made him happy again．______