While Shakespeare writes in blank verse in iambic pentameter, he varies it so that it is sometimes challenging to find large blocks of text that are written in regular, unvaried iambic pentameter. Shakespeare might vary his verse through the use of:
- hypercatalexis, which is adding an extra unstressed beat at the end of a line (five and a half meters): "But he'; / as lov' / -ing his' / own pride' / and pur' / poses,";
- catalexis, which is lessening a line by one or more beats (four and a half meters): "For -sooth', / a great' / a -rith' / -me -ti' / cian, __";
- acephalous, which is the omission of the first unstressed beat in a line: "__ Horri' / -bly stuff'd' / with ep' / i -thets' / of war'";
- lines that have a different meter, such as iambic dimeter: "And what' / was he'?"
He also liberally employs elision to blend several syllables into one beat, often by dropping an unstressed vowel or syllable. "I" and "am" are elided in "I am worth": "I know' / my price', / I_am worth' / no worse' / a place'."
Shakespeare also may fill an unstressed beat with the English pause, indicated by a comma, semicolon, colon or em dash.
Having said this, here is an early excerpt of a speech by Othello that is in iambic pentameter--with--all manner of variation from acephalous (first line) to hypercatalexis (most subsequent lines) to regular pentameter: "Shall out-' / tongue his' / com -plaints'. /'Tis yet' / to know',--".
Let' / him do' / his spite':
My ser' / -vi -ces' / which I' / have done' / the sign' / -iory
Shall out' / -tongue his' / com -plaints'. /'Tis yet' / to know',--
Which, when' / I know' / that boast' / -ing is' / an hon' / -our,
I shall' / promul -gate'-- / I fetch' / my life' / and be' /-ing
From men' / of roy' / -al siege', / and my' / de -mer' / -its
May speak' / un -bonn' / eted to' / as proud' / a fort' / -une
As this' / that I' / have reach'd': / for know', / I 'a / -go,
But that' / I love' / the gent' / -le Des' / -de -mon' / a,