You must fill out this order form.

这个订货单你要填一下。

《新英汉大辞典》

We must fill those gaps.

我们必须填补这些空白。

youdao

So, again, someone must fill the hole.

因此，有人必须再一次填补这个窟窿。

youdao

They must fill out a measurement form that requires leg measurements for boot orders.

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