Your mother ______ for you everywhere. Where have you been?
A. has looked
B. has been looking
C. looked
D. was looking
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Mr. Wang has a ___________daughter.
A. three-years-old
B. three years' old
C. three-year-old
D. three-year old
With the elevation of people's standard of living, cosmetics ____favorite topic, especially among women.
A. becomes
B. become
C. has become
D. have become
磁感强度沿闭合回路的积分不为零时，回路上各点的磁感强度都不为零。
A. 对
B. 错
顺磁质附加磁场的方向和真空中磁场的方向相同。
A. 对
B. 错
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