在等差数列{an}中,当a1=a5(r≠s)时,数列{an}必定是常数列,然而在等比数列{an}中,对某些正整数r,s(r≠s),当ar=as时,{an}不是常数列的一个例子是_________. 答案:解析:公比为-1的等比数列就满足条件,如:an=(-1)n,a2=a4=1.答案:an=(-1)n根据汉语意思,完成下列句子。1. 你愿意来我家吗? __________ you like to _________ to my home?2. 他通常和家人共度周末. He usually __________ the weekends _______ his _________ .3. 彼得每天有一节英语课. Peter __________________ English lesson.4. 音乐教室在二楼. The Music Classroom is ___________ the.5. 他有多少本书? How many _________________________ he got?