单项选择题They have been tightening their belts for months, adapting themselves to a war economy.
单项选择题Unlike the common cold, flu tends to start abruptly.
单项选择题Poor children should not be deprived of the opportunity to participate in sports whenever possible.
单项选择题As an assistant in a shop, she tries to be courteous at all times, even when she is very tired.
单项选择题The people who speak Esperanto(世界语) hope that the language someday will become the international language for trade, science, and diplomacy.