单项选择题
Generally speaking, ______ immigrants cannot totally cut the tie with their motherland and be assimilated by the foreign culture.
单项选择题 If the whole framework of the thesis ______ beforehand, a great deal of time and energy would have been saved.
单项选择题 Bit by bit, a child makes the necessary changes to make his language ______.
单项选择题 He managed to save ______ he could to tend the homeless boy.
