1.He wants to learn music[改为同义句]

He [ would ] [ like ] to learn music.

解析：want to do sth = would like to do sth 想做某事

2.they realized [many things about China ] on our trip [对括号句子提问]

[What ] [ did ] they realize on the trip?

解析：原句时态是一般过去时,而且是对做的事情提问,所以用what did 提问

3.l hope to travel around the country. [改为同义句】

My【 hope 】【 is 】travel around the country .

解析：第一句中的hope是动词,同义句的hope是名词


希望能帮到你,祝更上一层楼O(∩_∩)O
有不明白的请继续追问,可以详谈嘛(*^__^*)为什莫是My【 hope 】【 is 】travel around the country .wish is不行吗因为原句是hope，所以同义句最好也写hope，因为hope也有名词形式，当然wish 也可以。