Grammar Exercises

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Text B

Text A

UNIT 5. Fluid Dynamics

Speak Up! Discuss these questions with a partner.

Grammar Exercises

Exercise A.We use the Past Perfect Simple for an action that finished before another past action started or before certain time in the past. We use the Past Perfect Continuous to show than an activity or situation was in progress for some time before another past action interrupted it. Look at the sentences then answer the questions.

a Wendy had just arrived at the airport when her friend walked in.

b I decided not to see the film because I had read a bad review.

c The contestants had been living in the house for six months before they announcedthe winner.

d The fans had been waiting for their favourite celebrity all day.

Exercise B.Circle the correct words.

1. Nina hadn’t sung/hadn’t been singing for long when she was discovered and became a star.

2. The star had already given/had already been giving three interviews that day.

3. I had waited/had been waiting in line for concert tickets all morning.

4. Mike hadn’t been/hadn’t been going to the theatre before.

5. Rumours had gone/had been going around for some time that the singer was getting married.

6. Had you waited/Had you been waiting long in the stadium before the group arrived.

7. As soon as I had left/had been leaving the cinema, it started to rain.

8. No one knew that the famous scientist had started out/had been starting outas a shop assistant.

 

Think about a system you’re familiar with which contains fluid that at a higher or lower pressure than atmospheric pressure. What is the reason for having a positive or negative pressure? How great is a pressure differential, relative to atmospheric pressure? How is the pressure differential generated and maintained?

 

 

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