To forbid the cheating strictly in this important exam, the authorities have released a rule that students _________ bring any reference books and stationery into their classrooms.

We can hardly believe such a young boy ______ travel around the world all by himself.

The public transportation is very convenient in that big city , so there______be any difficulty in traveling around .

--- I hope Jim won’t mind lending you his new digital camera. --- He ___________. I have already borrowed one from my cousin, David.

Sometimes smiles around the world ________ be false, hiding other feelings like anger, fear or worry.