题目内容：

对话填空
Melisa-M Li Lei-L
M:Look!This looks so interesting.There are dragons and frogs on it.
L:Ah,it's a great invention of an cient Chine.
M:Really?When was it invented?
L:I think it _____ ______ in Han Dynasty.
M:What _______ it ________for?
L:Guess!
M:_______it_______ for holding water?
L:No,it_____ _______for testing earthquakes.
M:Really?But how?
L:Read this and you will know everything.
M:Wow.it's really amazing.

优质解答

was invented
does come
Does used
was used