Why do the Romulans and Klingons in some of the Star Trek films speak English they are Aliens

They ALWAYS spoke english in the original series. It's really not something that bothers me, but I did like how it was handled in ST6 during the court scenes.

I rather enjoy watching foreign films with subtitles, can't stand dubs

IIRC, the english dubbing on Nightwatch [Nochnoy dozor] was actually pretty decent. I guess they decided not to go the route of having every character sound like young over-excited girls.