1/ 1/2 can be read “a half” or “one half”.
1/3 can be read “a third” or “one third”
so can 1/4 be read “a fourth” or “one fourth”?
2/ Despite its antiquity, certain aspects of its construction make it one of the truly wonders of the world
=> I don’t understand why they use truly (an adverb) here. Is the sentence wrong?