— I regret _______ you that you failed the exam.

— How I regret _______ so much time playing computer games.

A．telling; wasting

B．telling; to waste

C．to tell; wasting

D．to tell; to waste

理想的眼镜材料( )

A．水晶
B．石头
C．光学玻璃
D．玻璃板
E．塑料