They were surprised that a four-year-old boy should work out such a difficult problem ____ they themselves couldn’t.
--- What's one fourth and a half, do you know? --- Yes, it's _________.
Now children, turn to page ________ and look at the _______ picture in Lesson Two.
Both of the two rulers are broken. I want to buy a _______ one.
December is the __________ month in year.
--- What is the date today? --- It's _________.