题干
All schools in our province ______ new English textbooks to improve students'
listening，speaking，reading and writing abilities three years ago.
listening，speaking，reading and writing abilities three years ago.
A：admired
B：adopted
C： admitted
D：afforded
答案(点此获取答案解析）
B
定义域为R，且对任意
，
恒成立．则下列选项中不恒成立的是（ ）