ABOUT:
■ 中 by itself means "inside" or "in." However, when attached to a noun, it adds the meaning of "during" or "while" or "throughout." It is either pronounced as
ちゅう or じゅう. There appears to be no set rule for when to use either pronunciation. Learn a few examples by heart.
HOW to use:
■ Add to nouns or phrases to indicate duration or coverage.
EXAMPLES:
彼は、一日中、テレビを見ました。
He watched TV all day long.
[throughout]
仕事中なので、彼は外に出られません。
He is working, therefore he cannot leave.
[work-during-therefore-he-outside-cannot leave]
[during]
来週中に、宿題をすませましょう。
Sometime in the next week, let's finish the homework.
[next week-during-homework-let's finish]
[during a future time]