Changes the end position of the range.
var result = textRange.moveEnd(/* see parameter list */);
String that specifies the units to move, using one of the following values:
character - Moves one or more characters.
word - Moves one or more words. A word is a collection of characters terminated by a space or some other white-space character, such as a tab.
sentence - Moves one or more sentences. A sentence is a collection of words terminated by a punctuation character, such as a period.
textedit - Moves to the start or end of the original range.
Integer that specifies the number of units to move. This can be positive or negative. The default is 1.
Returns an object of type NumberNumber
Integer that returns the number of units moved
There are no standards that apply here.
Microsoft Developer Network: [moveEnd Method Article]