Are "branches and leaves" (지엽) important?

 ANSWER: Not according to Koreans

The Sino-Korean word 지엽 (枝葉) literally means "branches (枝) [and] leaves (葉)," but Koreans use the word to mean "minor details" or "nonessentials."

So, if you want to refer to something as "a minor problem," "a side issue," or "a mere detail," you can refer to it as a 지엽문제, which literally translates as "a branch-and-leaf problem."

From Dong-A's Prime Korean-English Dictionary (1998)

What is the Korean name for a "beech" tree?

ANSWER: 너도밤나무 

 The Korean word for "chestnut tree" is 밤나무, and the Korean word for a "beech" tree is 너도밤나무, which literally translates as "You are also a chestnut tree." Of course, a beech is not a chestnut tree, but the two trees are similar enough that they are sometimes confused, even though beechnuts are much smaller than chestnuts. Anyway, here is my translation of a story that Koreans use to explain the origin of the Korean name for a beech tree.

One day a passing monk sees a child and tells the child's father that the child is fated to be killed by a tiger. The shocked father asks the monk what he can do to save his child. The monk says that the father will have to save 1,000 people to change the child's fate. Realizing that it would be nearly impossible to save 1,000 people, the father asks the monk if there was anything else he can do. The monk tells the father that instead of saving 1,000 people, he can plant 1,000 chestnut trees, and that is what the father does.

Later when the tiger comes for the child, the father tells the tiger not to take his child because he has planted 1,000 chestnut trees. But, unfortunately, one of the trees has died, leaving only 999. 

Just as the tiger is getting ready to pounce on the child, a nearby tree says, "I am also a chestnut tree" (나도 밤나무다). Hearing this, the tiger leaves without killing the child. With tears of emotion flowing down his face, the father says to the tree, "Yes, you are also a chestnut tree" (그래, 너도 밤나무다).

By the way, there is also a small tree or shrub Koreans call 나도밤나무 (I am also a chestnut tree), which is different from a 너도밤나무 (You are also a chestnut tree). And there are other plants that Koreans have named using the 나도 (I also) prefix, which is a prefix that suggests the plants are similar but different than the names of the plants to which the prefix is attached. Below are just a few of them from my Korean-English dictionary:

Dong-a's Prime Korean-English Dictionary (1998)

  

Dong-a's Prime Korean-English Dictionary (1998)

What is the Korean word for "turtle": 거북 or 거북이?

 ANSWER: Both words mean "turtle."

My Korean-English dictionary says that the Korean word for "turtle" is 거북, not "거북이," but in the Korean proverb listed together with the definition of 거북 the word 거북이 is used instead of 거북.

"거북이 잔등의 털을 긁는다." 

"It is very hard to shave an egg."

The above translation of the Korean proverb is not a literal translation. Here is the literal translation:

"A turtle is scratching the hair on its back."

One of the problems with many Korean-English dictionaries is that they seem to be written for Koreans, not for foreigners. If my dictionary, for example, had been written for foreigners, then wouldn't it have also given the literal translation of the Korean proverb?

Anyway, why does my dictionary list 거북 as the Korean word for "turtle" and then use the word 거북이 for "turtle" in the proverb? Or is the 이 in 거북이 just the subject marker?

I have read that 거북 and 거북이 both mean "turtle" but that even though 거북 is more commonly found in dictionaries, 거북이 is more commonly used by Koreans.

I have not read this anywhere, but it seems the word 거북이 may come from the Korean adjective 거북하다, which means "to feel shy" or "awkward." Or maybe the adjective 거북하다 came from the Korean word for "turtle"?

Since turtles hide inside their shells when they are approached, they appear to be "shy," so 거북이 may literally mean "a shy animal" since the suffix 이 can mean "animal," "person," or "thing."

If true, then 거북하다 could translate as "turtlelike."