英语：将下列句子合并为带有宾语从句的主从复合句.谢谢!
1.Tony is good at math.Linda said.
Linda said ( ).
2.I will go to Qingdao.Mike said.
Mike said( )
3.Is it necessary to learn English well?Sally asked.
Sally asked()
4.Will Mr Lin come to our class?We don't know.
We don't know ()