A man in a button up shirt with a black shirt underneath presents in front of a television.
A man prepares to give a speech for a television audience.
The first sentence only implies the man is presenting in front of a television, not necessarily that he is preparing a speech for an audience.
Not everyone who presents information also prepares to give a speech. Not all who are in front of a television present for a television audience.
Just because a man is on television does not mean they're giving a speech.