Not "You are ready?" — say "Are you ready?". 提问的时候，am / is / are 会跳到句子最前面。
试一试: ___ I ready? (Am / Is / Are) 答案: Am — Am I ready? 用 I 要配 Am——而且提问时它要放在最前面。
Is he? Is she? Is it?
主语是 he, she, it（另外一个人或一样东西）时，用 Is 来提问。
Is he here?
Is she here?
Is it here?
Not "Are she here?" — say "Is she here?". he, she, it → Is。但 you 永远配 Are。
试一试: ___ he a teacher? (Is / Am / Are) 答案: Is — Is he a teacher? He 是一个人，所以用 Is 提问。
Are you? Are we? Are they?
主语是 we 和 they 时，用 Are 来提问。You 也用 Are，不管是一个人还是很多人。
Are you here?
Are we here?
Are they here?
Not "Is they here?" — say "Are they here?". we, they 和 you → Are，从来不用 Is。
试一试: ___ they students? (Are / Is / Am) 答案: Are — Are they students? They 是不止一个人，所以用 Are 提问。
回答“是”
先说 Yes, 再说人和 be 动词。be 动词后面没有别的词了，所以不能缩写：Yes, I am.
Yes, I am.
Yes, he is.
Yes, they are.
Not "Yes, I'm." — say "Yes, I am.". I'm 后面必须跟一个词。这里句子已经结束了，所以要说 Yes, I am.
试一试: Mei: Are you ready? Lars: Yes, ___. 选出合适的说法： (I am / I'm / I is) 答案: I am — 如果你选了 I'm——这个形式后面永远要跟一个词，可这里句子已经结束了。所以要说 Yes, I am.
回答“不是”
先说 No, 再说人和否定词。这里后面有 not，所以可以用缩写：No, I'm not.
No, I'm not.
No, he isn't.
No, they aren't.
Not "No, I amn't." — say "No, I'm not.". 没有 “amn't” 这种说法。用 I 的时候，说 I'm not。
试一试: Amina: Is Diego here? Wei: No, ___. 选出合适的说法： (he isn't / he aren't / he not is) 答案: he isn't — No, he isn't. He 是一个人，所以否定词是 isn't。
问题 → 回答
回答里要再用一次 be，用跟回答者自己的人称搭配的形式：Are you…? → I am。
Are you ready? — Yes, I am.
Is she here? — No, she isn't.
Not "Are you ready? — Yes, I is." — say "Are you ready? — Yes, I am.". be 动词要对上：Are you…? → I am. Is he…? → he is.
试一试: Hiroshi: Are Mei and Wei students? Camila: Yes, ___. 选出合适的说法： (they are / they is / they're) 答案: they are — Yes, they are. 问题用的是 Are，所以回答也用 are。"they is" 对不上，而简短的 Yes 回答也不会以缩写 they're 结尾。
试一试: Yasmin: Is Sofia ready? Ethan: Yes, ___. 选出合适的说法： (she is / she's / she are) 答案: she is — 简短的 Yes 回答以 be 动词结尾，所以不能缩写：Yes, she is. "she's" 是缩写形式，不能放在回答的末尾；而 she 也从来不配 are。