英语四级听力的练习：VOA慢速4.7

　　From VOA Learning English, this is the Tech Report.

　　Johannesburg is tweeting up a storm. The South African city leads the continent of Africa in Twitter usage. A new study shows that Johannesburg averages one tweet every 13 seconds.

　　The public relations company - Portland Communications carried out the study called How Africa Tweets. It gathered information about geo-tagged tweets from October to December of 2013. A geo-tag records position information of a tweet. The study shows that over 600,000 geo-tagged tweets were posted during the three months.

　　Allan Kamau leads the Nairobi, Kenya office for Portland Communications. He says it is no surprise that Johannesburg leads Africa inTwitter use. South Africa has the highest smartphone usage of any country in Africa.

　　Also, Egypt featured highly - Cairo, Alexandria, other top cities in terms of active tweeting. Moving to East Africa, Nairobi is the most active, not surprising. Its sixth most active on the continent, said Kamau.

　　But Mr Kamau says geo-tagged tweets do not represent the total number of tweets from each city. But he says, they do provide a dependable estimate of Twitter usage.

　　It should be a broad indicator of the trends within the Twitter sphere. Its representative enough for it to be a broad indicator of Twitter activity, trends in terms of how people are using it, said Kamau.

　　The company did its first study in 2012. Mr Kamau says the largest change he has seen is in how Twitter is being used.

　　In terms of topics, one of the shifts that weve seen is when we look at our survey in 2012 was that it was very much social conversations online. Were seeing much more corporate. Many more companies having a presence online, so brands having a greater share of voice, being more active, engaging consumers directly, said Kamau.

　　He says consumers are now using Twitter to discuss faulty products or bad services.

　　Its a much more public place, and also its a direct and public channel to complain. And people organize very well on social media, said Kamau.

　　Kamau says companies, organizations, and even sports teams - now value Twitter as a great resource for social involvement. The leading topic of Twitter across Africa is football - a sport known in the US as soccer.

　　Africans love football, are very passionate about their football teams, and Twitter provides a platform again for fans to get behind their teams.The most mentioned football team was Johannesburgs Orlando Pirates. Its just a fantastic platform for that kind of thing, said Kamau.

　　Mickey Modisane is the public relations director for the Orlando Pirates. He says the teams Twitter account has 145,000 followers. He says he is excited about his teams Twitter Popularity.

　　And thats the VOA Learning English Technology Report.