"用标签标明" can be translated into English as "label with a tag" or "mark with a label".
Here are a few example sentences to illustrate its usage:
Please label each item with a tag for easy identification.
(请用标签标明每个物品,以便于识别。)
The packages should be marked with a label indicating their contents and destination.
(包裹应该用标签标明其内容和目的地。)