1) "Beware the ides of March."

The soothsayer's warning to Caesar.
Act 1, Scene 2, line 18

2) "Yond Cassius has a lean and hungry look;
  He thinks too much: such men are dangerous."

Caesar giving his opinion about Cassius.
Act 1 Scene 2, lines 194-95

3) "Cowards die many times before their deaths;
The valiant never taste of death but once."

Caesar speaking to his wife Calphurnia.
Act 2 Scene 2, lines 32-33

4) "Et tu, Brute?"

Caesar as he is stabbed by Brutus.
Act 3, Scene 1, line 77

5) "Caesar's spirit, ranging for revenge,
With Ate by his side, come hot from hell,
Shall in these confines, with a monarch's voice
Cry, 'Havoc!" and let slip the dogs of war."

Antony speaking of the civil war that will follow Caesar's death
Act 3, Scene 1, lines 270-273

6) "Not that I loved Caesar less, but I loved Rome more."

Brutus speaking to the crowd, justifying the assassination.
Act 3, Scene 2, lines 21-22

7) "Friends, Romans, countrymen, lend me your ears;
I come to bury Caesar, not to praise him."

The opening words of Antony's funeral oration.
Act 3, Scene 2, lines 73-74

8) "For Brutus is an honorable man;
So are they all, honorable men."

Antony's ironic statement about the assassins.
Act 3, Scene 2, lines 82-83

9) "There is a tide in the affairs of men,
Which, taken at the flood, leads on to fortune;
Omitted, all the voyage of their life
Is bound in shallows and in miseries.
On such a full sea are we now afloat,
And we must take the current when it serves,
Or lose our ventures."

Brutus speaking to Cassius, advocating immediate action.
Act 4, Scene 3, lines 218-224

10) "This was the noblest Roman of them all."

Antony paying tribute to the dead Brutus.
Act 5 Scene 3, line 68.