Answer
1. He wondered how to tell the news to his parents.
- Câu tường thuật dạng Wh-word : S + asked O + Wh-word + S + V ( lùi thì )
- how to do sth : cách để làm gì
2. They can't decide who to go first.
- can (not) + Vinf : (không) có thể làm gì
- Wh-word + to V