选择题请说明原因1____wid
１．选Ｂ
despite不管，尽管．是介词,后加名词,或动名词，一般不接过去分词的形式
in despite of 固定搭配，不管，尽管
eg。Despite the bad weather,they had a good time。
though是连词,虽然,尽管，后接句子．widely used in the chemical industey 在这里是省略了主语 it is/sodium carbonate is ,因为主句和从句是同一主语，所以从句的主语可以省去
eg。 Though it was cold,they had a good time。
though (Tom ...全部
１．选Ｂ
despite不管，尽管．是介词,后加名词,或动名词，一般不接过去分词的形式
in despite of 固定搭配，不管，尽管
eg。Despite the bad weather,they had a good time。
though是连词,虽然,尽管，后接句子．widely used in the chemical industey 在这里是省略了主语 it is/sodium carbonate is ,因为主句和从句是同一主语，所以从句的主语可以省去
eg。
Though it was cold,they had a good time。
though (Tom was)young,Tom was good at doing this work。
这句话的意思是，虽然碳酸钠被广泛应用于化学也，但它主要在工业中使用
２．选Ｂ
known是过去分词做后置定语，也可以看做省去了which is,被知道
Helium is not flammable and, next to hydrogen, is the lightest gas
which/that is known。
如选Ａ 必须加kmown as the lightest gas
know as。。。固定搭配，称为，被认为
。收起
