be/come up against a (brick) wallto reach a point where you cannot make progress, especially because something or someone is stopping you 碰壁 We seem to have come up against a brick wall in this investigation. 我们这次调查似乎碰壁了。
be/come up against a (brick) wall• She swam in what she hoped was the direction of the stairs, only to come up against a wall.
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