词汇运用
⑴No one is____ （允许）to drive after drinking.
⑵As soon as I arrived in Hong Kong, I sent a ____ （信息）to Mum.
⑶About two hundred people ____ ( 死 )in Ya'an Earthquake on April 20^th .
⑷The moon light shines in ____(通过) the window and the room seems quiet and beautiful.
⑸The teacher spent a long time ____ (解释)the problem to the boys after class.
⑹Now Father's Day becomes very popular. It is on the ____ (three) Sunday every June.
⑺Teenagers should be encouraged to make decisions by ____ (they).
⑻It's much ____ (sun) this weekend. Why not go camping, David? ——Sounds great.
⑼Everyone likes Mary in our class because she always talks to others____  (polite).
⑽The telephone was one of the most important ____ (invent) of the 19th century.

下列各项中，属于有性生殖的是（　　）

在式子$\frac{1}{a}$，$\frac{2xy}{\pi }$，$\frac{3a^2{b}^{3}c}{4}$，$\frac{5}{6+x}$，$\frac{x}{7}$+$\frac{y}{8}$，9x+$\frac{10}{y}$，$\frac{x^2}{x}$中，分式的个数是（　　）