ɽɭֱɾսľ. ֻڿľĵطٻ˷. ׼һ, Ϳֻõһֻ, ڿɭֵĵطʹô˷.

жȫȻ, սֱɱ, Ҳ뿪ǱٻǸ. ǶԽƻȶԲǿ.

Ҫʹáٻ,  [ٻ] ͼʾϰ, Ȼ׼Ҫĵ˸ɭ. ӵҪ׼ɭһ<link="topic:line of sight">Ұ</link>.
