这些选项有什么不同呢？？ 麻烦啦
1.I sold all my houses___________A.by auctionB.at auction
2.It is difficult to convince them that it is ___________ for them to study this project.
A.worthy
B.worthwhile
3.They ________ the new president _________ the hope of the country.
A.see as B.consider as
4.Then Miss Harker lifted her head and addressed them all in a ____________ tone.A.graveB.solemn
5.__________ is a list of names that I have found involved in the illegal trade of cigarettes.A.Enclosed B.Wrapped inside
6.Alice will _________ making arrangement for the coming staff meeting of the factory tomorrow.A.manage with B.go about
正确答案是1.A 2.B3.A4.A5.A6.B
谢谢解释，有些帮助！
但是第3、5、4的另一选项为什么不对？
1. at auction拍卖;
sell sth by auction： 拍卖某物eg. I shall sell my house by auction.我将拍卖我的房子。
In 2008 the top ten carpets sold at auction ranged from $68, 500 to $4. 5m.2008年，拍出的十张最佳地毯，最高价是450万美元，最低价也有68500美元。2. worthy： 值得的；优秀的；有价值的，配得上的；杰出人物值得的 (worthy of值得…的)worthwhile ['w?:θ'hwail] adj. 值得做的，值得花时间的
