多音字组词。
难 nán ____ 重zhònɡ____
nàn ____ chónɡ____
将点B(5,-1)向上平移2个单位得到点A(a+b, a-b),则( )
-- You must be tired out after the climbing.
-- Oh, . I felt too tired to move.
谚语“风吹沙石跑,车轮比人高”反映的气候类型是( )