题目

根据句意及汉语提示拼写单词 1．Thursday is the     (第五) day of a week. 2．There is no money in my      (口袋)． 3．The food     (尝起来) so delicious. 4．We all like      (下雨的) days because we can stay inside to play chess. 5．What’s the     (差别) between Chinese and English grammar? 6．We saw many kinds of flowers at the     (底部) of the mountain. 7．It’s our duty to     (保护) their environment. 8．We wanted Tony to     (描述) something about the accident. 9．The life in the countryside is much     如图所示，四棱锥P-ABCD的底面ABCD是正方形，PA⊥底面ABCD，且PA=AB，E是PA的中点．（Ⅰ）判断直线PC与平面BDE的位置关系，并加以证明；（Ⅱ）求二面角E-BD-A的大小．