mary: i’m now in the sea. i can’t believe it! it’s so beautiful! what a colorful fish! it’s so lovely! little fish, don’t go away! oh, here comes a blue whale. wow, it’s so big! it’s bigger than my classroom. oh no! there is a shark! help! help!

　　     helen: what’s the matter, mary?

　　     mary: i saw a shark. its teeth are so big!

　　     helen: oh, it must be a dream.

　　     mary: …yes, it’s a dream.