In the market, vegetables are sold by _______ kilogram, I mean, by _______ weight.
Zhang Hong is said___________by heart 2000 words up to now .
They really have a great time too , designing everything , drawing the blue prints , ___________the angles and so on .
—Was it in 1969___________the American astronaut succeeded___________landing on the moon ? —Yes , that’s right .
.—Who did you stay with ? —___________.
—What about the books ? —Books of this kind well .