1. A. The first task asks for a letter to answer specific questions and ask about the friend's birthday plans. B. The second task asks for an email to thank the friend and invite them to stay.
2. A. The friend Peter will read the first letter. B. The friend Robert and his family will read the email.
3. A. The letter to Peter should include information about the student's summer activities and whether they had a good time. B. The email to Robert should include thanks for their hospitality and a mention of spending time together.
4. A. In the letter to Peter, questions can be asked about how he celebrated his birthday, what he did, or what his plans are. B. In the email to Robert, a question can be asked about when he would like to come and stay or if he has any plans to visit again.