你好!
1、当特殊疑问词作句子主语时,特殊疑问句的语序不变,句末用问号:
I am reading an interesting book.
——What are you doing?
Tom helped us solve the problem.
——Who helped us solve the problem?
2、这类特殊疑问句,变为宾语从句,从句必须用【陈述语序】.
What are you doing?
——Please tell me 【what (you are) doing】
Who helped us solve the problem?
——Please let me know 【 who helped us solve the problem】
祝你开心如意!