单项选择题
A. The Cherokee Indians. B. Tourists. C. Ben Sands. D. Scientist.
A. To select top students. B. To know who had received ordinary schooling. C. To put students in a right order. D. To make sure who required particular treatment.
A. They tell us which one of the tracks the universe will use. B. They enable us to alter the course of universe. C. They give us information about the lunar surface. D. They determine which course the universe will take in the future.