One of the biggest problems in food production has always been that people have no reliable access to exact information, ____________ is often the case in China.
She is _______ at her boyfriend.
He looks forwards every afternoon to _____ the flower-lined garden.
His face looks brown because he works ____ all day.
I'm not sure whether this is the room ________ she left her dictionary.
---Don't put the waste on the ground. ---Oh, I'm very sorry. I ________ the dustbin(垃圾箱) there.