Unit 9 My favorite subject is science基础知识巩固Ⅰ、词汇。A)根据句意及首字母提示,补全单词,使句子完整、正确。1. -How many students are there in your class? -F . Thirty boys and twenty girls.2. -What color is your new bike? -O .3. My best friend was born in 1994, so he is thirteen y old now.网4. Simon's parents are very b and d..