内容正文:
Section Ⅱ Using language
情态动词(2)
观察下面教材中的句子并体会它们的语法特征
(1)That is why Letters from Father Christmas could be the perfect book for those who regard Christmas as a special time of year.
(2)The letters were also beautifully illustrated—each must have taken its true author, Tolkien, a long time to complete.
(3)In another letter, Father Christmas complained about how he could not stop his helpers playing games with the toys instead of wrapping them up.
(4)Interestingly, the letters did not contain the usual warnings to children that they might not receive their presents if they were not good.
(5)Letters from Father Christmas tells us that as well as enjoying the adventures of Father Christmas, Polar Bear and other characters at the North Pole, we can all share the true spirit of giving at Christmas time.
(6)By expressing love for his children in such a special way, Tolkien may indeed have been the real Father Christmas.
【语法感悟】
1.句(1)中的could表示较委婉的推测。
2.句(2)中的must have taken 表示对过去情况的肯定推测。
3.句(3)中的could表示能力,此处为can的过去式。
4.句(4)中的might表示可能性较小的推测。
5.句(5)中的can表示能力,can意为“能够”。
6.句(6)中的may have been表示对过去情况的肯定推测,可能性较小。
一、must的用法
1.表示义务、命令等,意为“必须”,强调说话人的主观态度。其否定形式为mustn't,意为“一定不要、不准、禁止”。
◆You must finish your homework this afternoon.
今天下午你必须完成你的家庭作业。
◆You mustn't smoke here.
你不许在这儿吸烟。
2.表示肯定的推测,为“一定”。
◆It must have rained last night, for the ground is wet this morning.
昨天晚上一定下雨了,因为今天早上地面是潮湿的。
3.意为“偏要、偏偏”,表示讥讽、不耐烦等感情色彩。
◆Why must he go out in the bad weather?
为什么他偏要在这种坏天气出门呢?
[即时演练1] 单句语法填空/完成句子
(1)We must make good use of the available space.
(2)—It must_be John who is in the office.
—No, it can't be him.I saw him off at the airport half an hour ago.
(3)严禁孩子们在大街上踢球。
Children mustn't_play_football in the street.
(4)如果你非要知道,我可以告诉你真相。
If you_must_know,_I can tell you the truth.
二、can与could的用法
1.表示能力,意为“能、会”。
◆I can play basketball now, but I couldn't when I was young.
现在我会打篮球了,但小时候我不会。
2.表示推测,常用于疑问句和否定句,can't/couldn't表示“不可能”。
◆—Can he be our teacher?
——他有可能是我们的老师吗?
—No, he can't be our