iText中用文本块(chunk)、短语(Phrase)和段落处理文本；

文本块是处理文本的最小单位，由一串带格式（包括字体、颜色、大小）的字符组成；

短语由一个或多个文本组成，短语也可以设定字体，但对于其中已经设定的字体的文本块无效；

段落一个或多个文本块或短语组成，相当于Word文档中段落的概念，同样可以设定段落的字体大小、颜色等属性。另外也可以设定段落的道行缩进、对齐方式（左对齐、右对齐、居中对齐）。

-iText using text block (chunk), phrases (Phrase) and paragraphs with text　text block is the smallest unit of text processing, consists of a string formatted (including font, color, size) of the characters　phrase by one or more Text composition, phrases can also set the font, but the font has been set for which a block of text is invalid　paragraphs one or more text blocks or phrase composition, representing the concept of paragraphs in a Word document, the same can set the font paragraphs size, color and other attributes. Alternatively, you can set the paragraph indent Daoxing, alignment (left-aligned, right-aligned, center-aligned).