v. make flat or flatter
v. become flat or flatter
v. lower the pitch of (musical notes)
vi. 使...不活跃, 变平
vt. 弄平, 打倒, 使失去光泽
1. She used a rolling pin to flatten the dough for the cookies.
她用擀面杖把面团擀平，准备做饼干。
2. The construction workers had to flatten the ground before building the house.
建筑工人在建房子之前必须把地面压平。
3. He tried to flatten the cardboard box to save space in the recycling bin.
他试图把纸箱压平，以便在回收箱里节省空间。