Ex1:

1. If you are late again,you will lose your job.

2. I'don see anything because it is dark.

3. His parents are happy because gets a good job.

4. My dog always barks if he hears the strange sound.

5. She is late for working because she miss the bus.

6. She doesn't work hard because she is old.

7. If the homework isn't long and difficult I will finish on time.

8. She doesn't read books because she doesn't have enough time.

9. We don't go for a walk because it rains heavily.

10. If people stop using dynamite,the fishing and sea creatures will be well preserved.

1.If you are late again, you will lose your job.

2.I can't see anything because it's dark.

3.His parents are happy because he gets a good job.

4.My dog always barks if he hears the strange sound.

5.She is late for working because she miss the bus.

6..She doesn't work hard because she is old.

7.If the homework isn't long and difficult I will finish on time.

8.She doesn't read books because she doesn't have enough time.

9. we don't go for a walk because it rains heavily.

10. if people stop using dynamite, the fishing and sea creatures will be well preserved .

Ex2:

1.Because he was busy, he couldn't meet you.

2.Because she was sick, she went to bed early.

3.Because this test is difficult, nobody can do it.

4.Because the road is narrow, two cars can't pass each other.

5.Because the weather was lovely, we spent the whole day in the garden.

6.Because he has a toothache, he can't go to school today.