Accelerating car trouble!?

hi. i drive a super old honda accord...like a 92? and i've had it for a few years now. good body, good running. (well, for the most part).. it goes through funks where it doesn't accelerate very well. ESPECIALLY IF I AM AT A STOP LIGHT. a stop sign isn't as bad..but if i'm stopped for like a minute, then it's so hard to accelerate the car back up. it usually takes about 5 seconds for it to catch on, but then i jam all the way up to like 7 RPMs. does anyone know what could be wrong? i realize that it's an old car...but i'd like to fix it bc everything else works. p.s. it goes in reverse fine...and once it gets started, it goes perfectly fine as well. THANKS :)