What is the difference between 主菜 and 主食 in terms of food items?
主菜 is typically the best dish in a banquet, in biological terms, the proteins.
主食 is referring to carbohydrates, namely noodles or rice.
In China, we usually eat 主食 with some dishes, and the dishes are called 菜。The dishes could be meat, vegetables, seafood and so on, but not carbohydrates.
This is a newby answer.
- find a reliable dictionary.
- Compare all the different answers because some are context sensitive.
- Rule out the answers that relate to specific topics or subjects you are not dealing with and you are very close to the correct answer.
I am currently trying https://www.yellowbridge.com/chinese/dictionary.php Their answer to your question is:
主菜 = zhǔcài main course and
主食 = zhǔshí main food; staple (rice and noodles).
This is slightly different to zyy's answer in that there is no mention of a banquet. I suspect the choice between 主菜 and 主食 is not dependant on the number of people attending the gathering to share a meal or dinner, but maybe the importance of the meal or dinner? Such as the annual gathering of life-long friends to share a favorite delicacy compared to a simple family meal with one main dish at the end of a long hard days work?