Here's the solution to fill in the gaps:
- A: The correct word is "these". Lemons are part of the citrus family. There are oranges, limes and grapefruits in these family. So, the answer is 2.
- B: The correct word is "first". They came to Europe around the first century. So, the answer is 2.
- C: The correct word is "people's". These fruits are very good for people's health. So, the answer is 3.
- D: The correct word is "use". People often use lemon juice. So, the answer is 1.
- E: The correct word is "stop". It can stop fruits and vegetables from going bad. So, the answer is 2.
Answer: