She didn’t study hard, so she failed the exam.

1. If she had studied hard, she wouldn’t have failed the exam.

2. If she had studied harder, she would failed the exam.

3. If she didn’t study hard, she failed the exam.

4. If she studies hard, she would fail the exam.

We have never visited that museum before.

1. It is not the first time of me to visit that museum.

2. This is the first time we have visited that museum.

3. This is the first time we have never visited that museum.

4. I visited that museum before.

They were too tired to finish the project on time.

1. They were so tired that they couldn’t finish the project on time.

2. They were such tired that they couldn’t finish this project.

3. They were so tired that they could finish the project on time.

4. They were too busy to finish the project on time.

 You should finish your homework before going out.

1. You shouldn’t finish your homework after come home.

2. You had better finishing your homework before going out.

3. You must finish your homework before going out.

4. You had better finish your homework before going out.