The doctors in Shenzhen did all they ______ to save Yao Beina, a famous singer, but she still died.
I have ________ useful knife and my sister has _______ eraser.
The tall boy ______ you just met is my brother.
-- Peter knows much French. -- ________.
Which sign tells you to go straight ahead? A. B. C. D.
The new teaching building ________ before the new term begins.