Ответ:
1) He can't go for a walk now because he is studying for tomorrow's test.
2) They must be at the school gym now. They usually play volleyball on Fridays.
3) The postman has already delivered the parcel.
4) The students are leaving for New York tomorrow.
5) Nelly has been painting her room for the past two hours.
6) Now everyone is talking about Shaun White's achievement
in the X Games.
7) Be patient. The performance starts in five minutes.
8) James is not in. He is attending a seminar in Moscow.
9) I have helped elderly people a number of times since 2010.
10) I'm the eldest child! I support my parents by working in the local supermarket after school.