English ⇄ Polish Russian

lose train of thought stresses
idiom.	забыть мысль (Now where was I? I'm afraid I've lost my train of thought. Mira_G); забыть, о чём только что говорил (Mira_G)
lose one's train of thought
gen.	сбиваться с мысли (yurtranslate23)
amer.	путаться (Maggie)
idiom.	потерять мысль (DC)
inf.	потерять ход мыслей (Excuse me, I lost my train of thought. What was I talking about? Val_Ships)
make lose one's train of thought
inf.	нарушить ход мыслей (Your question made the speaker lose her train of thought. Val_Ships)

lose train of thought: 5 phrases in 3 subjects

General	3
Informal	1
Rhetoric	1