How many capital letters of the English alphabet can be written using straight lines only?

The modern English alphabet is a Latin alphabet consisting of 26 letters (each having an uppercase and a lowercase form).

ABCDEFGHIJKLMNOPQRSTUVWXYZ are the letters of the English alphabet. AEFHIKLMNTVWXYZ can all be written using straight lines which is a total of 15 out of the 26 in the English alphabet.

The English language was first written in the Anglo-Saxon futhorc runic alphabet, in use from the 5th century. This alphabet was brought to what is now England, along with the proto-form of the language itself, by Anglo-Saxon settlers. Very few examples of this form of written Old English have survived, these being mostly short inscriptions or fragments.

The letters A, E, I, O, and U are considered vowel letters, since (except when silent) they represent vowels; the remaining letters are considered consonant letters, since when not silent they generally represent consonants.