Chapter 8 情态动词
8.3 推测用法（二）：将来预测 （情态动词一般式）
8.3 推测用法（二）：将来预测（情态动词一般式）
（一）
对将来的推测，更确切地说应该是“预测（prediction）”，谓语形式也是用“情态动词一般式”，这与上一节讨论的对现在的推测的谓语形式一样。实际上，除了must，情态动词如will，should，may，might和could都可以表示对将来的预测。比如：
1 A: What did the weatherman say?
B: It will rain tomorrow.
It should rain tomorrow.
It may rain tomorrow.
It might/could rain tomorrow.
上述例句的确定程度同样是由高到低。比如，should在表示推断时，不如用will表示推断时的自信心强：
2 1） Tom will know the address. 我肯定汤姆知道地址。
2） Tom should know the address. 我想汤姆会知道地址。
比如，《时代周刊》（Time）对21世纪所做的预测中提到以下内容：
3 It is a near certainty that science will discover the aging gene and find out how to turn it off. The ethical problems of who shall live and who shall die and who can have children in a crowded world will be monumentally difficult to solve.
妙语点睛 这里我们看到，因为该周刊对人类将会发现致衰老基因及将会面临的问题很确信，所以都用了will。
我们再看看下列句子：
4 A: I hear Mary isn’t getting much support in her running against Steve in the election.
B: It is not over yet. I think she will make a come back.
妙语点睛 说话人B在这里用了will，表明自己相信玛丽一定会反败为胜（Speaker B expects Mary to win.）
5 A: Think it’ll rain tomorrow? I am sure it won’t.
B: But according to the weather report, it will rain tomorrow.
妙语点睛 说话人A很自信地说“I am sure…”，所以他在后面用了won’t。
6 This movie will be popular in China because it explores some of the differences between Western and Eastern culture and the changing from the traditional to the modern world. 预计这部电影将在中国大受欢迎，因为它探讨了东西方文化的差异以及从传统社会过渡到现代社会这一过程中所发生的变化。
7 If much more snow accumulates, the roads will have to be closed. 如果再有更多的雪堆积起来，那么肯定要封路的。
would表示确定程度较大的预测。请看例句：
8 New Year’s Superstitions
In many European countries, people believe that the first visitor on New Year’s Day would bring them either good luck or bad luck. A dark-haired man would bring good luck. A woman or a man with light hair would bring bad luck. So some towns would choose a man with dark hair to go quickly from house to house. After he makes his rounds, the houses would be open to other visitors.
妙语点睛 这里的前三个would都是表示推测。注意，在So some towns would choose a man with dark hair to go quickly from house to house. After he makes his rounds, the houses would be open to other visitors. 中的两个would不是表示推测，而是表示“意愿”，即属于情态动词的基本用法。
should表示确定程度较大的预测，相当于“很可能将会这样了（most probably the case）”。请看例句：
9 The results are expected tomorrow. We should know the results tomorrow.
10 He should have plenty of time to get to the station. 他应该有足够多的时间去车站。
11 They shouldn’t have any difficulty in finding the house. 他们找这个房子时不应该有太大的困难。
12 The job should be finished by next Monday. 下周一之前应该能够完成这项工作。
13 He is the best runner, so he should win the race. 他是最好的赛跑运动员，所以应该能赢得这个比赛。
14 The journey should take two or three days. 行程应该需要两到三天。
15 Your laundry should be ready for pick-up tomorrow. 你送洗的衣服明天应该可以来取。
注意，should在表示推测时，也翻译成“应该”，但这并不是表示义务或责任的“应该”，而是表示说话人的主观判断或推测。
may表示约50％确定的预测。请看例句：
16 Tomorrow’s computers may have something for your nose to enjoy. 未来的计算机可能就会使你的鼻子能够闻到气味。
17 This bridge may collapse in an earthquake. 这座桥可能会在地震中坍塌。
18 We may go camping this summer. 今年夏天我们可能去野营。
could/might表示很不确定（如只有25%）的预测。请看例句：
19 There might/could be a strike next week. 下周可能会有罢工。
20 I might be given a new job soon. 不久我也许就会找到新的工作。
21 Look at those dark clouds. It could start raining any minute. 看这满天乌云密布的，说不定随时会下雨。
22 A campaign on the harsh terrain of a nation as large as California could be longer and more difficult than some predict.
妙语点睛 这里说话人用的是确定程度最低的情态动词could，表示对未来战争局势的预测。
再比如，《时代周刊》对21世纪所做的预测中提到，在未来，父亲和母亲的角色恐怕会像恐龙一样消失：
23 Between in vitro fertilization and cloning, dads could become dinosaurs. Moms, too, with the possibility looming of an artificial womb.
妙语点睛 当然，这只是一种不是十分肯定的对将来的预测，《时代周刊》用词很谨慎，用了could，而不是will或should。真是难以想象，如果没有了父亲和母亲，人类的社会伦理将会是什么样子。
很多读者可能不理解句子“Moms, too, with the possibility looming of an artificial womb.”的结构，该句完整的说法应该是“Moms could also become dinosaurs, with the possibility of an artificial womb looming.”。介词短语of an artificial womb应该接在possibility后面，表述“人造子宫的可能性”。looming是一个分词，表示“可能存在”。整个短语with the possibility of an artificial womb looming其实是一个分词短语，作原因状语，来说明原因——为什么说母亲的角色也可能会消失。
同样要注意，在否定句中，can’t/couldn’t要比may not/might not的否定语气强烈。试比较：
24 1） We may not/might not go camping this summer. 今年夏天我们可能不去野营。
2） We can’t/couldn’t go camping this summer. 今年夏天我们不可能去野营。
（二）
值得注意的是，should表示说话人的一种合理的假设（the speaker’s reasonable assumption），因此它是用来对说话人所希望发生的事进行推断的。若将来的事件不是他所期望发生的，则不用should表示这种推测。比如例句22讲到的对未来战争局势的预测，如果说话人用了should，即should be longer and more difficult than some predict，就意味着他希望战争“越持久越艰难越好”。请比较下面的例句：
25 1） Let’s not go to the movie. It could be bad.
2） Let’s go to the movie. The film should be really good.
妙语点睛 在例句1）中，“电影可能不好”并不是说话人所期望的，所以不说“It should be bad.*”。在例句2）中，“电影好看”自然是人人希望的，所以说话人用should。
再如说：
There should be another disaster shortly. *
这样说话显得很别扭，因为它暗示说话人对灾难持赞许的态度。所以正确的说法应该是：
There could be another disaster shortly. 很快就会发生另一场灾难。
A: I have flushed cheeks and a slight fever.
B: You should be coming down with something. *
妙语点睛 B的回答有问题，因为说话人用了should，暗示A的生病症状是他所希望的，这显然不妥，所以B最好用could，might，may或must来表达。从下面的译文中我们也看到，尽管在汉语中可以用“应该”来表达不好的事情，但英文中不可以这样表达。
26 A: These summer days are getting to be more than I can take. It was even too hot to go to the pool yesterday.
B: Hold on, according to the weather report we should have some relief by the end of the week.
妙语点睛 “天气转凉”是人们所希望发生的，所以用了should。
思维总结
首先，表示对将来的预测的情态动词较多，除了must外都可以，比如could和might等这样的过去形式的情态动词都可以表示对将来的预测。
其次，不同的情态动词所表示的确定程度不同。
最后，要理解should用来对说话人所希望发生的事进行推断。
思维训练 8.3 Key
请判断下列句子中的should是表示“义务”的“应该”，还是“推测”的“应该”。
1. Should I invite our neighbors to the wedding?
2. Dogs should be kept on a leash in public.
3. If they mailed it last week, it should be here by now.
4. Those who have studied should find the test quite easy.
5. Why should we always do what they say?
6. She should have said“thank you”for the gift.
7. How long should it take to complete the task?
8. They say you should serve red wine with steak.