tists have advanced many theories about why human beings cry tears , none of ______ has been proved.

Remember this ,children ,carefulyou are , mistakes you will make .We know ,Miss Gao .

ps John’s notin. — _______. Look, the light is on.

The retired man donated most of his savings tothe school damaged by the earthquake in Yushu, ____the students to return to their classrooms.[ ]

He was ill _____ a week, and _______ theweek he ate almost nothing .