Yes, he was. See Act 4 Scene 6 for details.
There are no publicly known songs that specifically go with each scene of Hamlet.
Horatio, in Act 1 scene 1. Hamlet doesn't see it until scene 4. It has to be this way because in scene 2 Horatio tells Hamlet that he has seen the Ghost.
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Horatio plans to go meet Hamlet at Elsinore, which he does in Act 1 Scene 2. Horatio plans to meet Hamlet on the battlements, which he does in Act I Scene 4. Horatio plans to meet Hamlet at the play, and does in Act 3 Scene 2. Horatio has no plans to meet Hamlet in England.
The phrase "To be, or not to be..." comes from Act III, Scene i, as the opening line to the most famous soliloquy in all of the Shakespearean canon. Hamlet has just entered the stage, and the King and Polonius have just exited--there is a strong suggestion that they can hear what Hamlet is saying, ostensibly aloud to himself.
The Shakespearean character Hamlet says the phrase "To be or not to be" as part of an immensely famous speech in Act 3 Scene 1 of the play Hamlet. Whether he "belongs" to the phrase is something else, and I'm not sure exactly what that means.
Hamlet Act 3 Scene 1
The quote "To be or not to be, that is the question" is found in Act 3, Scene 1 of William Shakespeare's play Hamlet.
Hamlet, Act 2 Scene 2
Yes, he was. See Act 4 Scene 6 for details.
There are no publicly known songs that specifically go with each scene of Hamlet.
In Scene 2, Horatio tells Hamlet that he has seen the ghost of Hamlet's father walking the battlements. Hamlet is much amazed and insists on accompanying Horatio to the battlements to keep watch. That's what they are doing in Scene 4.
The beginning plot of Hamlet ended in the last scene of Act 5.
Horatio, in Act 1 scene 1. Hamlet doesn't see it until scene 4. It has to be this way because in scene 2 Horatio tells Hamlet that he has seen the Ghost.
Hamlet. See http://www.opensourceshakespeare.org/views/plays/play_view.php?WorkID=hamlet&Act=1&Scene=1&Scope=scene
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