1peter: you (have been telephoning) for ages. have you not nearly (finished)? jack: i (have not got) through yet. i (have been trying) to get our paris office but the line (has been ) engaged all morning. 2 ann (has failed) her driving test three times because she's so bad at reversing. but she (has been practising) reversing for the last week and i think she (has got) a bit better at it. 3 tom: i have often (wondered) why bill left the country so suddenly. peter: actually, i have just (found) out. 4 he (has been playing) the bagpipes since six o'clock this morning. he has only just (stopped). 5 why have you (not brought) me the letters for signature? have you (not typed) them yet? 6 tom (looking up absent-mindedly as mary comes in): have you been (sunbathing)? mary (crossly): don't be ridiculous! it (has been raining) all day! 7 a pair of robins (have been building) a nest in the porch since last week. i (have been watching them from my window since they began. 8 the police (have not found) the murderer yet, but the dead man's brother (has been) in the station all day. the police say that he (has been helping) them with their enquiries. 9 they (have pulled) down most of the houses in this street, but they (have not touched) the old shop at the corner yet. 10 tom is convinced that there is gold in these hills but we (have been searching) for six months and (have not seen) any sign of it. 11 i (have been waiting) for the prices of the houses to come down before buying a house, but i think i (have been waiting) too long and the prices are beginning to go up again. 12 peter (has been) a junior clerk for three years. lately he (has been looking) for a better post but so far he (has not found) anything.
Surveillance is a really important innovation in our times as it helps to closely observe a suspected spy or a criminal. Public cameras ensure public safety, Through surveillance cameras, the police can both prevent crimes from happening and can quickly solve criminal cases with material evidence. In addition, surveillance cameras protect against property theft, and vandalism. Well, surveillance also has it's disadvantages. It can cost a lot and cause problems with an individual's privacy. In addition, they can help and watch the crime or help police to arrive earlier, but they do not prevent it.
Surveillance is a really important innovation in our times as it helps to closely observe a suspected spy or a criminal. Public cameras ensure public safety, Through surveillance cameras, the police can both prevent crimes from happening and can quickly solve criminal cases with material evidence. In addition, surveillance cameras protect against property theft, and vandalism. Well, surveillance also has it's disadvantages. It can cost a lot and cause problems with an individual's privacy. In addition, they can help and watch the crime or help police to arrive earlier, but they do not prevent it.