on request

1.Catalogues of our books will be sent on request.

书籍目录承索即寄。

2.Catalogues of our books will be mailed on request.

书目承索即寄。

3.The band will play on request.

乐队会按点播节目演奏。

4.Personal Memex: Record everything a person sees and hears, and quickly retrieve any item on request.

具有人样：录下个人看切，而且可以按照要求迅速提取每个纪录。