Ответ:

1. On
2. to
3. for
4. during
5. through
6. in (interesting - IN the picture, but ON the postcard)
7. at (at=British English / on=US English)

Объяснение:

How`s it going? Yope you`re well. I`m great! On Tuesday we went on a shcool trip to Kew Gardens. It was an extraordinary experience. The place is enornous and there are thousands of plant species  there! We were there for over four hours, but I feel like there is still so much more to see and learn. There was a guide with  us during our visit. She knew so many things about each plant. It was cool! We saw a lot of beautiful flowers and trees, but we also saw some very strange ones as we were walking through the place. My favorite was the Venus Fly Trap, which eats mostly insects and spiders. Cool, right? It`s the one in the pictures I`ve sent you. Anyway, I`m going again at the weekend. How about coming along? Let me know........