3x²+4-5x²)+（-x³-3+2x²）化简

(3x²+4-5x²)+（-x³-3+2x²）
=3x²+4-5x²-x³-3+2x²
=1-x³
We often discuss after class football news
动词原形?
再问： 动词填空：Doing moring exercises ( ) (heip) us () (get)ready for the day
再答： helpful Doing moring exercises (helpful)us (get)ready for the day