Unit 1动词be的一般现在时我们常使用动词be的一般现在时谈论事实和状态。如：I am from China. 我来自中国。He is 12 years old. 他十二岁。We are very happy. 我们非常高兴。注意：主语可以是人称代词，也可以是名词，动词be要与主语保持一致。如：The little dog is very cute. 这只小狗很可爱。These apples are big and red. 这些苹果又大又红。如果主语是代词，在非正式行文中，动词be与前面主语可以缩写。如：I am =Im You are =Youre She is =Shes He is =HesIt is =Its We are =Were They are =Theyre动词be 一般现在时的否定句式是在be后面加not. 如：She is not tall. 她个子不高。They are not in the classroom. 他们不在教室里。在非正式行
