【推荐1】You can't judge a book by its cover, as the old ________ (格言) goes. （根据汉语提示单词拼写）

【推荐2】As the ________(谚语) goes, “________ (击打) while the iron is hot.”（根据汉语提示单词拼写）

【推荐3】As the s_________ goes, “No pain, no gain.” There’s no such thing as a free lunch. (根据首字母单词拼写)

【推荐2】The p________ before you leads to a world full of challenges. (根据首字母单词拼写)

【推荐3】B________（蝙蝠） play an important role in the ecosystem, especially in controlling insects at night, but they are also carriers of some deadly viruses. (根据中英文提示填空）