“就一般而言，历史事件随着时光流逝而意义日减。鸦片战争则不然，它是中国历史的转折”。这主要是因为中国(    )

变换句式有误的是（    ）

    There are many people in the bus. Some have seats, but some have to stand. At a bus stop, a woman gets on the bus. An old man hears the door and tries to stand up. “Oh, no ，thank you", the woman forces（强迫）him back to the seat. "Please don't do that. I can stand." "But, madam. Let me…,”says the man. "I ask you to keep your seat." the woman says. She puts her hands on the old man's shoulder. But the man still tries to stand up, "Madam, will you please let me？”“Oh, no," says the woman, she again forces the man back. At last the old man shouts（大声喊），“I want to get off the bus!”

①染色体的重要成分　 

②各种膜结构的重要成分　 

③主要的能源物质

④能组成多种酶     

⑤性激素的主要成分　     

⑥调节细胞代谢．