They may also have used wood and skins, but these have rotted away.
他們也可能用過木頭和獸皮，但這類東西早已腐爛殆盡。
新概念英語第四冊
Lesson 1 Finding fossil man
?? 句中詞匯解析
從本句中提取的重要詞匯
adv. 離開，遠離;在遠處;消失;
adj. 不在的;遙遠的;客場比賽;
?? a(on)+broad→在遠方；離去；不在
"In the hotel, the old men were drinking away as usual."
在旅館里, 這些老人和往常一樣喝個不停.
近義：abroad, out, outdoors, outside, without
adj. 用過的;習慣于;二手的;舊的;
v. 使用（ use的過去式和過去分詞）;常常，經常;
"Things ain't what they used to be."
現在情況不比從前了。
近義：outworn, worn, utilized, wonted, accustomed
反義：unused, unworn
n. 木材;樹林;木制品;
vi. 收集木材;
vt. 在…植樹造林;給…添加木柴;
adj. 木制的;失去理智的;
"Wood is a poor conductor."
木頭不是良好的導體。
近義：lumber, timber, fuelwood, firewood, wooden