"Pochopil, proč pláču."

Translation: He understood why I was crying.

[Crazy_Sage]

And why not "He understood why I am crying"? Shouldn't it be jsem plakal for was crying?

[A477]

jaký je rozdil mezi “chapnout” a “pochopit”? jen vid?

[deactivated user]

Chápat impf -> pochopit perf

[BrianG1941]

The question i have is when do you use present, imperfect or perfect in reported speech. In this example you appear to be using the present tense placu and translating it into english imperfect.

Also it seems in the first phrase you are using the perfect tense together with the present tense in the second phrase. Is this always the case?

[VladaFu]

The understanding and the crying were concurrent, hence the present tense.

[Stephen900455]

I wrote "He understood why I cry" and it was rejected. Meaning: when X happens, my response is to cry. For example: when I read news accounts of children dying, I cry. Not everyone understands why I cry but this man from the past understood.

[VladaFu]

It is enough to just report.