∵单项式-2a3b8与13anb5的次数相同，
∴n+5=3+8，
解得：n=6．
故答案为：6．
晚上当你头朝南睡觉时，你的脚朝______面，你的左边是______面，你的右边是______面．
Speaker A: Thank you for everything you’ve done for me during my stay here. Speaker B: ().
A. Oh, this is what I should do.
B. You are welcome.
C. Don’t say that. Actually I have done little for you.
D. I’m sorry for not having looked after you well.
