题目内容
当的介词或副词填空
________ present, there are not many milu deer ________ nature parks in China．
The environmental experts are trying to keep animals and plat ________ becoming endangered．
If we don’t protect pandas, they will die ________.
Jack and Tome are good friends, and they have a lot ________ common.
—I’m going to take the exam tomorrow.
—Good luck ________ your exam.
Their talk ends up ________ a joke.
