Everyone knows that _______ is dangerous to play with fire, but _______ is difficult is to prevent children from playing with fire.
The monitor said that the learning method he used improved his maths.
Meizhou Island is such a beautiful place of interest______ everyone likes to visit.
As one of the most popular artists in the US, not only_______ with her hit songs, but has inspired women with her devotion to charity.
______almost one hundred jin, the stone was moved by him alone.
The boy the first prize, but he was so careless as to make a foolish mistake.