Which flight ________ ? —I want to catch the 13:00

Tina，is that your book on the sofa—No, is in the bookcase.

The maths problems are too hard, only ______ people can work them out.

选出下列有关文学常识表述无误的一项

Is there a vaccine _____ pig influenza?, I’m anxious to know—– Don’t worry, there is a vaccine _____ for pigs against pig influenza