Thank you for your reply,now I have a try,only for reference .
After double :
1- 1♦=4-card ♦,weak hand with less then 8hcp
2- According to Gib CC,2♣=11+hcp
3- 2♦=4+♦ with 8-10hcp
4- 3♦=preemptive, 6-card♦ with less than 7hcp
5- 4♦=preemptive,7-card ♦,weakish hand with 0-5hcp