题干
Don't ________ too much TV. It's not good for your eyes.
A：watch
B：watched
C：watching
D：to watch
答案(点此获取答案解析）
A
Don't ________ too much TV. It's not good for your eyes.
A：watch
B：watched
C：watching
D：to watch
的夹角为
，且
,
，在
ABC中，
，D为BC边的中点，则
（ ）