IE Frequentives

[Das Baron]

What were some ways that PIE and PIE languages formed frequentive/iterative verbs? All I've been able to find is *-ey- used with an o-grade, which was also used to form causatives, however the daughter languages seem to have different suffixes, such as Old English -lian- (PGmc *-el-) and Latin -t- (e.g. specto "I observe", from specio "I look at"). I assume there were various suffixes that each daughter language used, with most likely being new formations created in post-PIE times. So, my question is mainly about what frequentive/iterative formations were used productively to form new verbs and which, if any, can be traced back to PIE. Thanks.

[Sleinad Flar]

The suffix -sk'e/o- had iterative value in a number of languages (Hittite, Homeric Greek) and possibly also in PIE. This suffix seems to have formed causatives (Tocharian) and inceptives (Latin) as well.

[Soap]

I suppose the PIE nasal infix -n- could be the original frequentative, even though it doesnt have that meaning in any descendant as far as I know .... thet very fact that it isn't reflected in any of the daughter languages is evidence that it could have been the original frequentative, whose meaning shifted to a simple present tense marker thus leaving a gap in the grammar which was filled by different new morphemes in each branch.

[Sleinad Flar]

^ I don't get that logic. Because a suffix DOESN'T have a certain function in all of the daughter languages, it MUST have had this function in the parent language?

[Salmoneus]

Would you not connect the present-tense nasal infix with the causative nasal infix? I assumed that these present tenses were basically causative forms of the aorist

[Sleinad Flar]

I would. The nasal infix seems to formed transitives from intransitive roots. It still has this function in Hittite.