Writing Systems of the World 2, Exercise 1: classifying the first scripts

Cuneiform: logo-syllabic. Signs could stand for whole words (logograms) or for
syllables, and many signs did both, plus determinatives marking a word's
category (Cuneiform article).

Egyptian hieroglyphs: a mix of logograms, phonetic signs (24 single-consonant
signs plus two- and three-consonant signs) and determinatives. Because vowels
were normally not written, some scholars call it an abjad; the article notes
it is debated whether vowels were written at all.

Neither fits one box because early scripts combine meaning-based and
sound-based signs in the same text. Chapter 1 made the same point: most
systems are mixed, and the type names a tendency, not a rule.