2.[句型展示] By the year 2030, development in biochemistry and medical science will have made it theoretically possible for us to live for at least 150 years. 到2030年,从理论上讲,生物化学和医学的发展将使人类至少活到150岁成为可能。 [典例背诵] We all believe it necessary for us to master English. 我们都认为掌握英语是很有必要的。