The problem had become _____ in his mind, and he could not decide what to do about it.

When Jack arrived _____the airport，he found it hard to look for a place to park his car．

The Belt and Road is a new force of promoting the development of the world economy, that will further push China’s opening-up.

Do you know the name of the boy _______ father is a doctor

I feel really nervous before the interview.—- __________, sure. You’re the best.