Amy is from the UK. She's ______.
A:a student
B:new teacher
C:a boy
下面描述光合作用过程的反应式,正确的是( )
Present at the historic meeting ________ many an official on Nov 7, of course President Xi Jinping and Ma Ying-jeou ________.
下列事例中,那一项会通过食物链引发生态变化( )