读《鸟鸣涧》,王维的山水诗多以画入诗,这首诗描写了____、____、____、____等景物,通过衬托的手法,突出了山涧的____
下列物质的用途主要是利用其化学性质的是 ( )
Don't worry about him. He's old enough to __________ himself.