Emphatic adverb "ke"

可 can be used like 很 to add emphasis to an adjective, or like like 真 to add emphasis to a verb. It is stronger than other modifiers, as 可 compares the speakers expectations with the actual situation. The meaning of 可 is very reliant on context.

In these examples, 可 is used a bit like 很, as it is used to emphasize an adjective:

• 这 只 小 狗 可 淘气！(I never expected dogs to be this naughty)
• 哇，这 个 糖醋 鲤 鸡 可 好吃 啊！（I'v never dreamt that sweet and sour pork could taste this good)

In these examples 可 is used a bit like 真, and used to emphasize a verb:

• 你 可 来 了! At last! I never expected it would take so long for you to get here,
• 我 可 没 想 到 小 李 会 跟 他 女友 分手 I wouldn't in a million years think that they'd split up
• 你 可 别 喝 太 多 酒 (I'm expecting you to drink a lot)
• 你 可 别 走 (I'm blocking your way, almost pleading with you, as I believe you are going to leave)

In the last two sentences 可 is used with 别, and sounds a bit like "don't even think about..." in English

可 is generally used by Northern speakers, and is informal, generally only used in spoken Chinese.