B: You
very disappointed when they finally announced that Gore lost.
7. be
A: Yes, I was. What about you? Who did you vote for? B: I
8. work
overtime that day, so I didn’t vote. Anyway, one person’s vote doesn’t
matter much. A: It always matters!
6.7 Ability and Possibility in the Past EXAMPLES
EXPLANATION
President Lincoln could give good speeches. He also had a good sense of humor and was able to make people laugh.
In affirmative statements, could + the base form means used to be able to. It shows ability or knowledge over a period of time. Was/were able to can also be used for ability over a period of time.
In October 1962, President Kennedy was able to prevent war. He was able to convince the Soviets to send back their missiles.
In affirmative statements, we use was/were able to for success in doing a single action. We don't use could for a single action.
I couldn’t understand Lincoln’s speech. Were you able to understand it?
In negative statements and questions, could and was/were able to are used interchangeably.
Our history test could have been much harder. I could have given a longer presentation, but I wanted to stay within the time limit.
We use could have + the past participle for an action that was possible but didn't happen.
Some people thought that Kennedy couldn’t have won the election without TV. And maybe Barack Obama couldn’t have won without social media.
We use couldn’t have + the past participle to show that something was impossible in the past.
A: My grandparents liked to watch President
Couldn’t have + the past participle is used to show disbelief or to disprove a previous statement.
Roosevelt on TV. B: They couldn’t have watched him on TV. There was no TV back then.
EXERCISE 10 Circle the correct words to complete each sentence. In some cases, both choices are possible, so circle both options. 1. I (couldn’t use/couldn’t have used) social media last night because I didn’t have an Internet connection. 2. W e listened to the Gettysburg Address online, but we (couldn’t understand/couldn’t have understood) it. The vocabulary was difficult for us. 3. D o you mean you listened to Lincoln’s voice? You (couldn’t listen/couldn’t have listened) to Lincoln’s voice. There was no recording of his voice. You must have listened to someone else reciting the Gettysburg Address.
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