1. If current Olympic champion, Marion Jones, took such drugs, she would probably have broken that world record more than once.

2. Unless we are careful, "gene-therapy" will be the next big threat.

3. If gene-therapy were used now, it would be almost impossible to find out.

4. If a generation of sports stars with enhanced genes were created, it would contradict the whole spirit of sport.

T: Great. You have done a good job.

In this period, students are expected to review some conditional sentences they have learned before, and then they will learn different usage of the real and unreal conditionals. If students want to know more about the usage , they can read the detailed explanation that are included in the appendix (附件). Teachers may distribute them to students for reference.

Step Ⅱ The conditional sentences

Show the students the sentences they present above on the screen and have them find out the differences among them. It aims to help them to tell the differences among them.

T: Now I will show you some sentences on the screen. Please read these sentences and compare the different ways in which the conditionals are expressed then point out the real and the unreal conditionals. Do you know what the differences between the real and the unreal conditionals are?

S: The unreal conditionals are sentences in which the form of a verb expresses wishes, possibility and uncertainty.

T: Quite right. They are all introduced by the word "if". The unreal conditionals are sentences in which the form of a verb expresses wishes, possibility and uncertainty while the real conditionals are the sentences or clauses that begin with "if" or "unless" and express a condition.

T: Now let's turn to page 35, Ex 5. Read the sentences in Exercise 4 , can you describe the situations that are true or could possibly happen? Or can you describe situations that are imaginary, unreal or contrary to the facts?

Sample answers: