Now, everybody, please turn to page _________and look at the ___picture.

Children’s brains can’t develop properly_______ they lack protein(蛋白质).

She showed the visitors around the museum, theconstructionhadtaken more than three years.

Mrs. Green. Do you think I can get an “A” in the exam if I start working hard now— Of course. _________.

In such a fierce competition, aperson has to make every effort if he_______.