1. I am sorry that I didn't contact you lately, I was overwhelmed(压倒的意思) by my work. 2. He immediately turn on his computer after he reached home to do his maths. (现在式) He immediately turned on his computer after he reached home to do his maths. (过去式) 3. He have no time to (play/watch television) with you for he is busy typing script on his computer. 4. I am busy cooking, I don't have time to (talk to,可以换成:play with) to you. 5. What is keeping you busy? You wouldn't pick up calls and reply messages. IN=在的意思 In this classroom= 在这教室里 I am in here=我在这里 be busy 其是不正确,通常是 I am busy with my homeworks =我在忙着做功课 除非 be busy前面加 to, to be busy= 要忙 to be busy with house chores. 我要忙着做家务了.(还没发生的事)