The man looks so old that. I guess he must be _____sixty years old. [ ]
The World Expo (世博会) was openedMay 1st, 2010. [ ]
You’d better _______smoking, ______you will get ill.
There’ll be ______ one-hour documentary tonight on TV . It tells a story of _____ honest boy in the mountain village far away .
Of the two girls over there, the one in green is _________.