Where did most immigrants come from between 1820 and 19737 .
Most immigrants came from______.
According to the author, except global warming and privatization of water,______is also responsible for fresh water shortage.
She looked at her five children with (evidence) ______pride on her face.
People view tourist landscapes in a different way from ______.
I can not help (wonder) ______whether the doctor will come in time.
The abundance of food may be disastrous to farmers because of