单选题 You have worked so hard. You ______ a good rest.

单选题 The math problem is so ______ that I can't solve it easily.

单选题 Children should be under proper ______ when playing outside.

单选题 The sudden loud noise that night really ______ me.

单选题 The new stadium requires a ______ amount of money to build.

单选题 In the meeting, he always tries to ______ the discussion.

单选题 Over a long period of time, species ______ to adapt to their environments.

单选题 This documentary is very ______. It teaches us a lot about history.