请教３道王海波语法题

calliejuUID: 2150958

１．Allan Pinkerton, <founder> of <the famous> detective agency that bears
<him> name, directed a Civil War espionage system <behind> Confederate lines.
我知道ＨＩＭ　不对，但我还觉得，ＦＯＵＮＤＥＲ　前应加冠词啊

2. <Researchers> at the University of Colorado <are investigating> a series of
indicatiors that <could> help <themselves> to predict earthquakes.
答案Ｄ，　我觉得ＣＯＵＬＤ　应该改成ＣＡＮ　啊，请教

３．＿＿＿＿wooden buildings helps to protect them from damage due to
weather.
A. Painting B. Painted C. The paint D. By painting
答案Ａ，　Ｂ怎么不对了，？？

yuhang3650UID: 2165177

这些都是王海波单项训练里的题啊，你仔细听的话就知道答案了
1、the 可加可不加
2、情态动词永远不错，你不用考虑
3、painting buildings和painted buildings 表示的主语不一样