单选题
New volcanoes may appear ______ people do not expect them to be.
[A] whenever and wherever
[B] when and where
[C] whatever and wherever
[D] in when and where
【正确答案】
A
【答案解析】[名师精解] whenever=at any time when; wherever=in any place where，选项B中的when和where只能作关系副词，不能既作关系副词，又作appear的状语。 [解题秘籍] 凡是加了-ever的疑问词都有名词和关系代词或副词的功能，如：whoever=anybody who; whatever=anything which (that)。