Why does the lake smell terrible?—Because large quantities of water________.[ ]

Remember this, boys and girls. _____careful youare, _____mistakes you will make.—We know, Miss Wang.

You may use the book as you like, _______ you keep it clean

Look at this! It’s broken now! You ________ have been careful!

After Ya’an earthquake the school practiced anemergency drill showing the children how to findtheir “safe place”____.