_____no modern technology, the Egyptians had to move each stone by hand[ ]

Most birds find it safe to sleep in the trees, but ________they have eggs or young chicks, they don’t use a nest.

31．—What’s the matter with Christine—A letter from her parents inCalifornia________an attack of homesickness.

One of the ________ in our class ________ from America.

September 11, 2001 is the day ______ we will never forget.