Why is the speaker of England not allowed to speak?

The speaker in the House of Commons is the chairman. His/her role is to keep the debate flowing and to make sure that people get the chance to have a say in a debate and that the rules of debate and behaviour are adhered to. In other Words no name calling etc.

The speaker is supposed to be impartial, even though he/she is a member of one of the political parties, and so they do not get to give their own opinions on the debate.

However the speaker does speak. They will call out the names of the MP's (or at least their constituency) when he (or she) is telling them that it is their turn to speak and the speaker will tell off MPs for bad behaviour. The speaker can have MP's ejected from the house if they persistently break the rules.