Present passive

Study these sentences. 1. The radar sends out a beam of radio waves. 2. The information is stored on a smart card.   In1the verb is active and in2it is passive, the Present passive. Why is this so? What difference does it make? In1the agent responsible for the action is included – the radar. In2the agent is not included although we know what it is – the microprocessor. The passive is often used to describe the steps in a process where the action is more important than the agent and where the agent is already known to the reader. If we need to add the agent, we can do so like this: 3. The information is stored on a smart card by the microprocessor.  

I Underline passive forms in the sentences.

1. Computer systems are used in a wide variety of work situations.

2. Hospitals can increasingly use computers where highly trained people were required to deal with life-threatening situations.

3. Computers can also be used in airports where highly trained experts were previously required to ensure safety.

4. The barcode number system giving standard price and item code numbers used throughout Europe is known as EAN (European Article Number).

5. The barcodes are read by scanner devices called barcode readers that are attached to the EPOS tills.

6. A computer database is a type of applications program used for storing information so that it can be easily searched and sorted.

7. The item and the price are shown on the EPOS till display and printed on a paper receipt.

8. The scanner signals are converted to a digital form and sent to the supermarket branch computer.

9. In some systems, radar equipment is used to bounce radio waves off the moving car.

10. A lot of information can be stored on a smart card.

II Use the correct tense-forms of the verbs in brackets.

1. Computers (to use) to provide cash to users and to process bank cards such as Visa cards using an automatic teller machine.

2. A microprocessor (to calculate) the speed of the car from the changes in the radio waves.

3. When the smart card (to take back) to the police station, the driver’s details (to obtain) from the DVLC.

4. New systems (to prevent) ‘surfing’ i.e. where the driver only (to slow) down as they (to pass) through the speed trap.

5. The registration numbers of vehicles exceeding the speed limit immediately

(to download) to the computer at police headquarters.

6. At police headquarters each vehicle (to match) with the Driver and Vehicle

Licensing Centre database.

7. Standard letters then (to print off) addressed to the vehicle owners.

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