double back

• • 往回走，顺原路折回(或逃走)：

    The escaped boy doubled back on his tracks.

    那个逃跑的男孩突然循原路折回。

    She doubled back to see if she could find the missing watch.

    她顺原路折回看看能否找到丢失的手表。

  • 把…对折，折叠；把…反折：

    It ruins a book to double back the pages as a bookmark.

    把书页折起来当作书签用会把书弄坏的。