In the Aramaic of the Babylonian Talmud, there is a widely used word "קא", like in the sentence והא קא קרי (in Berahot 13:1).
What is the best way to translate it to Hebrew or English? Or maybe just skip it?
(Moved from comment section):
The word קא indicates that the action is on-going or in the state of being done. It corresponds to the English prefix a-, which used to be used much more frequently but now is uncommon in the English of the northern United States yet it is still very common in the English of the southern United States.
Here are some examples in English taken from songs and demonstrating all tenses: 1. She was a-rocking and a-rolling. 2. I'm a-coming right now. 3. We will be a-singing and a-dancing all night long.
It has also been incorporated in some words, such as aglow, alight, and afix.
For translating the Aramaic, you could do one of at least three things:
Omit it: Its absence won't make that much difference in English. You might, however, need to add something to the translation of the entire passage in order to be clear that the action is or was in the state of being done. For example, "He was reading when something happened" (i.e., you'd add the word 'when' to clarify that the reading was on-going at the time something else happened).
Use the Old English / Southern United States prefix: "He was a-reading, and something happened." (Note that the 'when' can now be changed to 'and' or even omitted and we still understand that the reading was on-going when something happened.)
Insert further clarifying words, such as: "He was in the process (or, in the act) of reading (and) something happened." These clauses can also be broken into two seperate sentences, as they often are in Aramaic.
Actually, the fact that the Aramaic often seems to be presenting the narrative as two seperate sentences may be why you'd want to translate it as "in the process of" or something like that. If you omit it, the on-going / concurrent nature of the action is not as strongly emphasized, as in:
That's why you might want to translate it as: