单项选择题
We live in a time______, more than ever before in history, people are moving.
单项选择题 ______of the students in our class are from the north.
单项选择题 ______you feel too ill to go out, I would rather not stay at home tonight.
单项选择题 Don't leave matches or cigarettes on the table within the______of little chil-dren.
