first you must know what are they!
they are "fi3l madhi nakis" "incomplete past verbs"
they are us use: with nominal sentences, they put the sentences in the past, and keep the meaning of state or information
nominal sentences are "sentences without verb and give an information, it doesn't contain actions (there are rules for exceptions)
for the influence: the 2d name (el-kahbar-the information-) will have "fat7a" and not "dhama"
you must know some thing about "djoumla ismia"
for the meaning thanks for RANA, for the use if you need more informations ask plz