on request

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

书籍索即寄。

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

书索即寄。

3.The band will play on request.

乐队会按点播节演奏。

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

具有人样的记忆：记下个人看到和听到的切，而且可以按照要求迅速提取每个纪。