_____ they keep the water clean. ____ they make the tank look much prettier.

A. For; And 　 B. For one thing; And

C. For; Also 　 D. For one thing; Also

— I saw a beautiful fish in the street market the other day. It was orange and blue. I'm thinking of buying some next Sunday.

— Where would you keep them?

—  61  

— It's a bit small, isn't it?

—  62 

— I think you should get a tank (水箱 ) if you want to keep fish .

—  63  

— Yes , You should never keep fish in a small round bottle . They don't get enough air. I suggest we go shopping together and look for a nice tank.

—  64

— Check the prices before you buy one . And you ought to get a few large rocks to put in the tank . Fish love swimming round the rocks and through holes in them.

—  65  

— Yes , you need to get some underwater plants . For one thing they keep the water clean . Also they make the tank look much prettier.

A . I haven't decided at all.

B . In that round bowl over there.

C . Is there anything else that I ought to get?

D . Really?

E . So are the fish .

F . That might be quite expensive .

G . What else should I do then?