1. She cannot cook because she feels very tired today. => If she __________________________________________

If she were not very tired today, she could cook.

In this sentence, we are dealing with a conditional statement that reflects a situation contrary to fact. The speaker implies that her current state of fatigue prevents her from cooking, and therefore, if her condition were different—if she were not tired—then she would have the capability to cook. This is an example of the second conditional, which is used to discuss unreal situations in the present or future.

In Vietnamese, this could be expressed as: "Nếu cô ấy không quá mệt hôm nay, cô ấy có thể nấu ăn." This translation maintains the same logical conditional structure, indicating that her current tiredness is the reason for her inability to cook.