【题目】My grandfather still plays tennis now and then, he's in his nineties.
A.as long as
B.as if
C.even though
D.in case

【答案】C
【解析】题目考查状语从句。句意：即使是九十多岁了，我的爷爷仍然可以时不时地打打网球。as long as 只要，引导条件状语从句；as if似乎，引导方式状语从句；even though即使，引导让步状语从句；in case以防，引导目的状语从句。这里是转折关系，故选C。