●问：下面这个句子里，第二句里的it is today在句子里是什么成分？句子是什么意思

   The degree of an industry is based upon the ability of that industry to move forward through continual advances and developments in new technology. The porcelain enamel industry is a good example of such a success story where innovations in technology have controlled its progress and brought it to the viable business it is today.

    ☆答： it is today在句子里是定语从句，省略了关系代词that，先行词是   the viable business。全句含义是说：搪瓷业的成功，正是由于工艺技术的革新掌握了这一工业的进展，使它成为今天这样一个具有生命的企业。