The development of industry has been ____gradual process throughout _____ human existence, from stone tools to modern technology.
Do you remember those days we spent very happily along the seashore last summer?
I' ll never forget Mr. Smith, help we had made great progress.
In our class, when the bell rang and the teacher closed his book, it was a for everyone to stand up.
The new dictionaries are very useful. They well and already.
Every year a flood of farmers arrive in Shenzhen for the money-making jobs theybefore leaving their hometowns.