used for后加什么形式

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

　　一些空间将首先用于贮藏。

　　The money saved could be used for more deserving causes.

　　省下的钱可以用于更需要帮助的事业。

　　It looks like the pictures were being used for blackmail.

　　看来这些照片正被用于敲诈勒索。