在素描中，有哪些技巧是必须掌握的，哪些是鲜为人知，可否分享一下

First of all, you should understand the basic knowledge of sketch. For example,the connatural colour,the colour of lamp-house,the environmental colour.There is another one which called point, line, surface, or value,and the relationship of them.
what is unknown skill? Absolutely, CULTURE. That's the greatest difference between limner and artist.
At last ,I want to tell you that a respected artist, in addition to his technical excellence, the more important thing is his charisma.

大关系最重要，然后是细节的刻画，注意眼睛、颧骨的转折，要有凹凸的感觉，多临摹点书，最好是美术学院出版的那种

很负责的告诉你，没啥鲜为人知的技巧可言，在中国我们画画不是为了追求艺术，而是为了考学，老师教你怎么做你就怎么做，千万别想要什么风格技巧，否则到最后只能是泪的代价！

What s the fuck !

U shiting me?

We don't know the fucking English!

Understand, asshole!

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