9. Using 4 digit 4s and some addition, subtraction, multiplication, division signs, and parentheses, write five expressions whose values are $2$, $3$, $4$, $5$, and $6$ respectively.
Analysis: $4 \div 4+4 \div 4=2, \quad(4+4+4) \div 4=2, \quad 4+(4-4) \div 4=4, \quad(4 \times 4+4) \div 4=5, \quad 4+(4+4) \div 4=6$