Does 出太阳时候不能吃饭 (chū tàiyáng shíhòu bùnéng chīfàn) express "I can't eat when the sun is out" appropriately?
Question: Does 出太阳时候不能吃饭 express "I can't eat when the sun is out" appropriately?


Not completely, because '出太阳' (sun is out) can refer to 'sun coming out after the storm' That implies you can still eat as long as you don't see the sun (when it rain or the sky is cloudy) 

The correct way to explain it is:

太阳仍在天空时不能進食 (can't eat when the sun is still in the sky)

or 

太阳下山前不能進食 (can't eat before the sun had gone down)

or 

天黑前不能進食 (can't eat before the sky is dark -meaning the sun has completely set)

or 

日落前不能進食 (can't eat before sundown)


Replaced 吃饭(to have meal) with 進食 (to eat), because  不吃饭(not having meal) doesn't cover having something for a snack.


user6065 wrote:


  从日出到日落不进食、 (不喝)水，不吸烟


' Not eat, drink or smoke from sun rise to sun set' is the more detailed explanation of fasting.

Mindless wrote:


  出太阳时候 = daylight? Can't you just say 白天不能进食, can't eat during daylight？  


白天 refers to 'daylight time' (after the sun has completely risen and the sky is totally bright, or before the sun started to sink below the horizon and the sky is still bright). The term 白天 does not including the twilight time of dawn and dust, therefore it is not suitable for describing the fasting hours