Conditional Sentences

1. ConditionalSentences then if

2. Agenda • Definition • Types and Uses • Case1: First Conditional—probable • Case2: Second Conditional—impossible • Case3: Third Conditional—no longer possible • Exercise • References

3. Definition • Conditional sentences contain two sections • The main clause gives the result of the condition. • The conditional clause explains the condition. • Conditional clauses usually begin with if, unless, provided that, or a similar conjunction. Conditional clause result If the smoke gets too bad, we will have to stop soldering. We cannot continue this experimentunless we wear protective masks. result Conditional clause

4. Clauses • Conditional clauses can be at the beginning of a sentence or at the end of a sentence. result Conditional clause We will have to stop soldering if the smoke gets too bad. If the smoke gets too bad , we will have to stop soldering. result Conditional clause

5. First Conditional—PROBABLE • The condition refers either to present or to future time. Hence, it can become true. • The sequence of tenses is: • Main clause (result): future tense • Conditional clause (condition): simple present tense Conditional clause = condition = simple present tense If we finish the design today,we will be able to start development tomorrow. Let’s do it! Main clause = result = future tense

6. Second Conditional—IMPOSSIBLE • The condition will not be met and is impossible. It is stated in the simple past tense. • The sequence of tenses is: • Main clause (result): would + verb • Conditional clause (condition): simple past tense Conditional clause = condition = simple past tense Argh! We can’t do it! If we finished the design today,we would be able to start development tomorrow. Main clause = result = would + verb

7. Second Conditional—WERE • Usage of “were” for a singular noun is a special case • Use “were” in the conditional clause only for an impossible statement • The sequence of tenses is: • Conditional clause: If + were • Main clause: would + verb If I were rich, I would buy a Porsche. – not likely When I was rich, I bought a Porsche. – this did happen! If platinum were not so expensive, more circuits would be constructed with it.

8. Third Conditional—TOO LATE • The condition can not be met any more because it is too late. It is stated in the past perfect tense. • The sequence of tenses is: • Main clause (result): would + have + past participle of the verb • Conditional clause (condition): past perfect tense But it’s too late now. Conditional clause = condition = past perfect tense If we had finished the design today,we would have been able to start development tomorrow. Main clause = result = would + have + past participle of verb

9. Passive Voice • Using Passive Voice in If-Clauses can make the tense-sequence grammar very difficult! Future passive voice Soldering will have to be stoppedif the smoke cannot be controlled. Present passive voice Would + passive voice Soldering would have to be stoppedif the smoke could not be controlled. Past passive voice Would + past perfect passive voice Soldering would have had to be stoppedif the smoke could not have been controlled. Past perfect passive voice

10. Exercise If the phased locked loop ______ (not find) to be a useful element in may types of communication systems, this technology _______(not gain) so much popularity. If it ________ (apply) correctly, it ____ (become) useful in two fundamentally different ways: 1. It can serve as a demodulator, if it ____ (use) to follow phase or frequency modulation and 2. it can serve to track a carrier or synchronizing signal which may vary in frequency with time. If it ______ (operate) as a demodulator, we _____ potentially______ (can use) the phase locked loop as a matched filter operating as a coherent detector. If it______ (use) to track a carrier, we _________ (can employ) it as a narrow-band filter for removing noise from a signal. If, in the old days, Newton _________ (make) such a discovery, today’s engineering world _______ (see) a much wider use of this technology. (adjusted from Mills, Thomas B. (1971). The Phased Lock Loop IC as a Communication System Building Block. National Semiconductor Application Note 46. Available http://www.national.com/an/AN/AN-46.pdf.)

11. Answers If the phased locked loop had not been found (not find) to be a useful element in may types of communication systems, this technology would not have gained (not gain) so much popularity. If it is applied (apply) correctly, it will become (become) useful in two fundamentally different ways: 1. It can serve as a demodulator if it is used (use) to follow phase or frequency modulation and 2. it can serve to track a carrier or synchronizing signal which may vary in frequency with time. If it were operated (operate) as a demodulator, we could potentially use (can use) the phase locked loop as a matched filter operating as a coherent detector. If it were used (use) to track a carrier, we could employ (employ) it as a narrow-band filter for removing noise from a signal. If, in the old days, Newton had made (make) such a discovery, today’s engineering world would see (see) a much wider use of this technology.

12. More Information • http://ccc.commnet.edu/sensen/part4/esltips/esl_conditional.html • http://www.ccc.commnet.edu/grammar/conditional2.htm • http://web2.uvcs.uvic.ca/elc/studyzone/410/grammar/2cond.htm • http://www.bartleby.com/64/pages/page266.html

13. Conditional Sentences: Quiz • Please take the Conditional Sentences Quiz on WebCT now.