位于糖酵解、糖异生、磷酸戊糖途径、糖原 合成及分解各代谢途径交汇点上的化合物是A．6

____________ many times, but he still couldn't understand it.[ ]

A. Though he had been told

B. Having been told    

C. Having told

D. He had been told

使儒家思想逐渐成为古代社会的正统思想开始于             [ ]

A．秦始皇      

B．汉高祖     

C．汉武帝       

D．唐太宗

预防措施有哪些具体内容？

下列汉字编码标准中，不支持繁体汉字的是（）

A、GB2312-80

B、GBK

C、BIG5

D、GB18030

Which of the following is true

A．A representative serves for two years.

B．To become a senator is easier than to become a representative.

C．A senator performs his duties for a shorter time than a representative.

D．All presidents were representatives and then senators before becoming president of the United States.