One of the quirks of Sumerian is that things are often referred to twice, once as substantives and once as affixes to the verb. The following example comes from Gudea Cylinder A (column ii, line 4) courtesy of the ETCSL.
The individual signs were pronounced something like this:
ma2-gur8-ra-na ĝiri3 nam-mi-gub
Those signs are only an approximation of the pronunciation. Sumerian writing had a fairly loose fit to the spoken language. Even though it is an agglutinative language, forms in Sumerian did sometimes change depending on the neighboring sounds. (Again, this should not be so alien to students of Greek or Latin, with forms like Latin rex where two consonants /g/ and /s/ have merged together over a short vowel /i/, or all those assimilated verb forms which are the terror of students of Greek). Combining the signs for individual words and affixes together, we get something like this (most Sumerologists will tell you that other elements were spoken but not written down, or were assimilated with the ones written down, and some would prefer to translate the expression ĝiri3 gub differently than the individual words of which it is made, but I think that this is close enough for a blog post).
magur–ani–a ngiri na–mu–ni–gub
And a literal translation would be: “He really set his foot on it, on his barge.” (Put your mouse over words in the second version to see the meaning of individual elements).
This sort of thing is not completely unfamiliar. In Latin Caesar venit, iste venit, and venit are all natural ways of saying “that guy over there came.” Latin verbs indicate the person and number of their subject with inflection, and whether to indicate the subject with a separate word was a matter of style and emphasis. But Gudea and his scribes were fairly consistent in marking objects twice, once as a separate word and once as a prefix to the verb.