only在句首要倒装的情况
Only in this way, can you learn English well.
Only after being asked three times did he come to the meeting.
如果句子为主从复合句,则主句倒装,从句不倒装
Only when he is seriously ill, does he ever stay in bed.
From:https://www.zgghmh.com/CET-4/20001599.asp