47．In order to catch up with the leaders of the social—networking industry，such as Facebook and Twitter，Google determines to enter into__________ by launching Buzz．
48．The move of Google becomes a sign that the world of social networking is _________with the world of other online services．
49．According to the data provided by comScore，the numerous Gmail users can easily create a network via_________.
50．The filtering ability from Buzz enables Gmail users to_________．
51．Those who already have their social networks elsewhere won’t easily_________