Three.
54. What are they?
To separate the parts of a compound word; to separate a word into syllables; and to divide a word at the end of a line.
55. When should the Hyphen be used in a compound word?
When the word has not become permanently compounded.
56. When use the Dieresis instead of the Hyphen?
When the syllables are divided by the hyphen, there is no hyphen used between the vowels of the digraph.
57. What is the use of the Period?
To denote an abbreviation.
58. Are there any other uses of the Period?