填空 be used for /be used by /be used to/used to
Mother______ beso forgetful.
In many countries,English is_______ the second language.在许多国家,英语被用作第二语言.
Chinese the largest number of people in the world.汉语被世界上最多数的人使用.
She_______ take a walk.
She_______ taking a walk.(现在习惯于散步)
An orange_____ medicine.桔子可以入药.
A seweater______ keeping warm.毛衣是用来保暖的.