Answer the Questions

I. Where did Jack and Arnold meet?

2. What is Jack's field?

3. How many astronauts did NASA lose in the Challenger accident?

4. Were all the Challenger passengers astronauts?

5. Why didn't the O-ring seals on the rocket boosters work?

6. Did the space program get back on its feet fairly soon after the Challenger tragedy?

REGULAR AND IRREGULAR VERBS

Use the simple past tense when you want to talk about something that happened at a specific time in the past. Here are some time expressions that we use with the simple past tense.

yesterday, last night (____) ago

the day before yesterday last week a minute ago

last month two hours ago

last yeara few days ago

Affirmative Statements

REGULAR VERBS

In English there are both regular and irregular verbs. Most verbs are regular. To form the simple past tense of a regular verb, add - ed or - d to the base form.

IRREGULAR VERBS

Many common verbs have a completely different form in the simple past tense. They do not add - ed or - d to the base form to form the simple past. Turn to the Appendix for a list of the most common irregular verbs and their endings.

⁶ O-ring seals are giant black rubber Os that help stop gases from escaping from the four segments (pieces) of the rocket boosters.

⁷ Setback means «some problem that stops progress».

⁸ Fairly soon: After thirty-two months of hard work, the United States was back in space with the successful flight of the space shuttle Discovery on October 6, 1988.

⁹ NASA is the National Aeronautics and Space Agency.

IRREGULAR VERBS

Many common verbs have a completely different form in the simple past tense. They do not add - ed or - d to the base form to form the simple past. Turn to the Appendix for a list of the most common irregular verbs and their endings.