请教两道英语题
He colleted the facts ___proved the earth and all the other planets move around the sun.
为什么空格里既可以写that也可以写 which啊,什么情况下只能用that或只能用which
还有一题
Is this the museum____they visited last month?
为什么空格里只能填the one 而不能填which
谁能帮帮我,O(∩_∩)O谢谢