4 . Look at the HELP box and then complete the gaps in this summary of the text on operating systems using these linking words and phrases :
Although |
because |
but |
in addition |
such as |
therefore |
The user is aware of the effects of different applications programs and know how to use them …………………. operating systems are invisible to most users . They located between applications programs , ........................ database management , and the hardware . The supervisor program is the most important . It remains in memory , ............................ it is referred to as resident . Others are called non-resident ............................ they are loaded into memory only when needed . Operating systems manage the computer ' s resources , ................... the central processing unit . ............................., they establish a user interface , and execute and provide services for applications software . ........................ applications programs , they are carried out by the operating system . Every general-purpose computer must have an operating system to run other programs and applications . For large systems , the operating system has even greater responsibilities and powers . It is like a traffic cop -- it makes sure that different programs and users running at the same time do not interfere with each other . The operating system is also responsible for security , ensuring that unauthorized users do not access the system .
5 . Here is a list of typical tasks performed by an operating system . Each case the main verb has been omitted . Fill in the blanks from the words given . Sometimes more than one may apply .
HELP BOX
We use but to show a contrast , because to show that the next idea is a reason and so to show a result . Other words and phrases used I this way are : however ( contrast ), therefore ( result ), although ( contrast ) Contrasting ideas : We can use the following language techniques to contrast ideas : Clauses of contrast :
� These consist of two clauses : the main clause and the contrast clause . Even ᇣᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇤᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇥ though the number of mobile phones users has Increased, call ᇣᇧᇧᇧᇧᇧᇧᇧᇧᇤᇧᇧᇧᇧᇧᇧᇧᇧᇥ charges remain high. contrast clause main clause
� The main conjunctions of contrast are : although but even though though whereas while
� Notice the difference in use between but and the others :
Videoconferencing ᇣᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇤᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇥ is very convenient, but ( ᇣᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇤᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇥ it ) is not as personal as face − to − face contact . main clause main clause
Although ᇣᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇤᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇥ videoconferencing is very convenient, it ᇣᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇤᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇧᇥ is not as personal as face − to − face contact . contrast clause main clause
1 . _____________ input and output devices . 2 . _____________ the status of hardware devices . 3 . _____________ hardware interrupts . 4 . _____________ new disks . 5 . _____________ disk directories . 6 . _____________ disk reading and writing operations . 7 . _____________ disk errors .
8 . ______________ disk commands relating to the deletion , copying , renaming , and dumping of files .
9 . ______________ for security , ensuring that unauthorized users do not access the system execute monitor format diagnose responsible
A typical operating system will :
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