你好: 1 I'd like to volunteer 【to help that old man】。 2 At 12:00 midnight , I called my friend 【to go out for a walk】。 3 I'm very busy but I could help 【to do some housework】。 4 Summer vacation is coming , and I want 【to pay a visit to the Great Wall】。 5 I want to travel alone .My parents told me (not)【to drink cold water】。 不清楚的请追问哦! 希望对你有帮助!满意请采纳!