The key answer of exercise 5

a)

1. That's something
2. I'm always
3. but
4. people think think much of
5. I've wasted
6. get over

c)

1. Sara was late because of her alarm clock wasn't working properly.
2. You should make sure you put things in your calendar in order to remind you to do them.
3. Yuan went to the cinema early to get a good seat.
4. Take your car keys so that as you can drive if you get tired of walking.
5. You need to study hard so as to get a good test result. / You need to study hard so to get a good test result.
6. Because I was late, I waited until the break to go into class so as not to upset the other students.
7. In order not to disturb the boss, don't talk outside that room - she's in an important meeting.
8. We use an online meeting maker so as to get agreement from everyone on the best time to meet.