used for后加什么形式

　　Some of the space will at first be used for storage.

　　一些空間將首先用于貯藏。

　　The money saved could be used for more deserving causes.

　　省下的錢可以用于更需要幫助的事業。

　　It looks like the pictures were being used for blackmail.

　　看來這些照片正被用于敲詐勒索。