改错，句中缺少单词，请在恰当位置添加。
Millions upon millions people excitedly got to the square at the wonderful news.
A big bear ran out from a tree.
He came on foot instead of bike.
—Are you sure that our team will win?
—Yes. I'm sure it.
The headmaster wasn't present the meeting yesterday.
Xiao Ming is preparing the exam while his mother is preparing supper.
改错，有一个词是多余的，请选出。
The next day she returned the book back to the library.
You may begin with Step by Step first to improve your listening.
Help yourself to eat some fish, Mr. Jones.
In winter, if you put a mirror in the front of your mouth, you'll see it covered at once with little drops of water.