(2012年江苏南通九校联考)When ________different cultures,we often pay attention only to the differences without noticing many similarities.
I have seen trees, _____ open at sunrise and close at sunset.
___ is known to all, China is a developing country, belonging to the third world.
She showed her new watch to my wife, ___ was kept in a box.
The reason ______he didn't come was ______he was ill.
We travelled together as far as Chicago, _______ we parted.