The beautiful girl _________came here last Saturday is my friend.

Look! He’s jumping so far!—Hard to ________ his legs were once broken.

________ that he found it difficult to stop at thebusy crossing.

When he saw the front cars ________ in the traffic jam, he decided to make a detour (绕路).

The government of the United States began at once to investigate the case ______ a lot of students were killed.