【推荐1】The ______ (封面) of this book is well-designed.

【推荐2】We can't judge a book from its ________ (封面).

【推荐1】When we post letters, we should use s_____.

【推荐2】—How many ________ (熊猫) are there in China？ —Sorry, I don’t know.

【推荐3】Complete the sentences with the given words in their suitable forms
1. We’d like to have more modern science __________ in our school.   (laboratory)
2. It’s __________ to waste so much time and money. (necessary)
3. He needs courage (勇气) and __________ to climb the mountain.   (strong)
4. The sun ________ behind a cloud, and then it became dark. (appear)
5. Simon, you’ve made so many mistakes in your homework. I’m so ____________! (disappoint).
6. I think it would be possible to have a enjoyable and _________ school life.   (colour)