một điều quan trọng nên nhớ là 
an important thing to remember is ~ [ một ] : one; a, an
[ điều ] : (1) thing, matter, item; article (of penal code, constitution); (2) smoking pipe; (3) bird [=chim]
[ quan ] : (1) official, officer; (2) franc (unit of currency); (3) coffin; (4) sense
[ trọng ] : heavy, important; to think high of, hold in esteem
[ nên ] : (1) ought to, should, had better; (2) candle; (3) so, that’s why, consequently, so, therefore, (4) become
[ nhớ ] : to remember, recall, miss
[ là ] : that; to be
Most Common Compounds Set 1:
Most Common Compounds Set 2 :