Question

what did authors wife advise when food was serve to them during flight​

Answer 1

to open the lid carefully because he always split the food allover while opening lid.

Answer 2

The authors wife did advise something at the time when food was served inside the flight. She asked to open the lid carefully.

This is because the author was not proper in matters of serving food and always split the eatables when opening the lid of the box without the attention. It is important for the author to be cautious when dealing with the tiffin box.