______ remains doubtful ______ this is an important discovery.

The ________ looks on her face suggested that Mary ________ the birthday gift from her mother.[ ]

We understand _______small changes to our land can have a big impact upon our environment __________ as we know is vulnerable enough.

依次填入下列横线处的语句，与上文衔接最恰当的一组是（ ）学好文科关键是要有很强的记忆和理解能力，刘言和李莉两位同学各有所长， 。

Do you want music in the music room