Loss of appetite is sometimes a sign of illness.食欲不振有时是生病的征兆。

That walk has given me an appetite.走了那段路使我胃口大开。

He has a healthy appetite.他胃口很好。

the country's seemingly insatiable appetite for raw materials该国对原材料的需求似乎永无止境

He clearly has an appetite for adventure.他显然渴望冒险。

She gave him just enough information to whet his appetite.她向他透露的信息刚好能吊起他的胃口。