The teacher spoke loud and clearly enough to make himself ________ by all his students.
A：hear
B：heard
C：hearing
D：to hear
— Well, I like Yi Yangqianxi best, because I think he is ___________.
某同学牙疼，牙龈上出现了一个“脓包”，这个“脓包”主要由什么构成（ ）
（2015•包头）下列说法正确的是（ ）
