ThecollegestudentsinChinaare_______fromsmokingoncampusbecausethiswilldothemnogood.
Freemedicalserviceis_______tonearlyallthecollegestudentsinChina.
Sometimesitisverydifficultto_______someoftheEnglishwords.Eventhenativespeakercannothelp.
Whenmakingmoderncameras,peoplebeganto_______plasticsformetal.