<\body> <\explain> <|explain> This primitive inserts an elastic vertical space after the current paragraph. All operands must be . The argument specifies the default length and the and arguments the bounds to vertical stretching for page breaking and filling. If and are not specified, then they are determined implicitly from the length unit of . Notice that operands are not evaluated, so they must be literal strings. <\explain> <|explain> This primitive is similar to , except that the vertical space is inserted the current paragraph. The actual vertical space between two consecutive paragraphs is the , not the sum, of the vertical spaces specified by the the and tags in the surrounding paragraphs. <\explain> <|explain> This primitive inserts an empty box whose width is , and whose bottom and top sides are at distances and from the baseline. If and are not specified, then an empty box is inserted whose bottom is on the baseline and whose height is the same as the lowercase letter in the current font. Notice that operands are not evaluated, so they must be literal strings. <\explain> <|explain> This primitive inserts inserts a stretchable horizontal space of nominal width , which must be a . The and arguments specify bounds to horizontal stretching for line breaking and filling. If and are not specified, then they are determined implicitly from the length unit of . Notice that operands are not evaluated, so they must be literal strings. <\explain> <|explain> Springs are horizontal spaces which extend so the containing paragraph takes all the available horizontal space. When a paragraph is line wrapped, split in several visual lines, only springs in the last line are extended. A spring has a and a . If the weight is 0, the spring is , otherwise it is . If a line contains mixed weak and strong springs, only the strong springs extend.\ The fraction of the available horizontal space taken up by each strong spring is proportional to its weight. If there are only weak springs, they share the available space evenly. <\indent> inserts a strong spring of minimal width and of weight unity. The operand must be a . specifies the weight, which can be a positive decimal number or one of the two special values documented below. > inserts a spring, only the first one in a paragraph is significant. > inserts a spring, only the last one in a paragraph is significant. Operands are not evaluated and must be literal strings. Weak springs are useful in style-sheets. For example, tail weak springs are used to make the list environment extend to across the full paragraph, so vertical motion commands in nested lists behave as expected. In regular documents, springs are often used to place some text on the right side of the page and some other text on the left side.