The stamp was a dark, dull blue colour with a heavy black postmark.

这枚邮票是模糊的暗蓝色的，上面盖着一个粗黑色的邮戳。

《柯林斯英汉双解大词典》

Hurstwood's shoes were of soft, Black calf, polished only to a dull shine .

赫斯渥脚上穿了一双黑皮鞋，是用柔软的小牛皮做的，只擦得微微发亮。

youdao

It was not dull grey as distance had suggested, but a mottle of khaki and black and olive-green.

那其实不是从远处看起来的暗灰色，而是黄褐色、黑色和橄榄绿组成的杂色。

youdao

Published immediately after September 11, 2001, the cover depicts the Twin Towers as rich black silhouettes on a dull black background.

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"Looking at a black line all day, every day gets awfully dull, " he said.

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