I heard him, but only vaguely.

我听到了他说的话，但只是模模糊糊的。

youdao

The exact size of these industries can be estimated only vaguely, but their scope and impact cannot be denied.

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Thus, the debate became not only one about taxes, but vaguely about welfare programs in general.

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But I know, vaguely (online only, just to be clear) one of the authors.

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