Read the following passage and put the verbs in the correct form, present perfect or past simple. (5 marks) then and now twenty years ago few people realized (realize) that computers were about to become part of our daily lives. this short period of time has seen (see) enormous changes, in business, education and public administration. jobs which ) weeks to complete in the past, are now carried out in minutes. clerks who (spend) all day copying and checking calculations are now freed from these tedious tasks. in offices, the soft hum and clicking of word ) the clatter of typewriters. schoolchildren (become) as familiar with hardware and software as their parents (be) with pencils and exercise books. computerization of public records (enable) government departments to analyze the needs of citizens in details. some of us may wonder, however, whether life (really/improve) as a result of these changes. many jobs (disappear), for example, when intelligent machines (take) over the work. employers complain that clerical staff (become) dependent on calculators and cannot do simple arithmetic.