The letter was handwritten in black ink.

这封信是用黑墨水手写的。

《柯林斯英汉双解大词典》

Holmes thought deeply on the way home: the story of the Hound, Sir Charles's death, the strange letter, the missing boot and the black bearded man.

在回家的路上，福尔摩斯沉思着猎犬的故事、查尔斯爵士的死、那封奇怪的信、丢失的靴子和那个黑胡子男人。

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The black paint had run down in little sharp points beneath each letter.

写字用的黑色颜料在每个字母下面都流成了一个个小尖头。

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Yellow or brown areas shaped like the letter V on leaves may be a sign of black rot infection.

VOA: special.2009.03.03

Having said that, howsabout we now turn to the tedious task of examining the black letter law of forgery?

FORBES: Line Between Signature And Forgery Trips Up Former Wells Fargo Broker

"These are the lowest head coach diversity numbers the league has seen since 2003, when the Rooney Rule was just implemented, " wrote Harry Carson, the Fritz Pollard Alliance's executive director, in a letter to NFL officials regarding the drop from six to four black head coaches in the league after this past regular season.

CNN: In dark day for NFL diversity, Newsome shines

There is a letter written by Jack Johnson, the legendary black boxer, in which he confesses that he had thrown a famous heavyweight title fight against Jess Willard in 1915.

ECONOMIST: Forget Gauguin. Sotheby's has Gehrig's jersey