An accident is holding fill preposition traffic.
I am surprised that you fell (fill prepostion)that trick.
The investigation team is.(fill prepostion)lose to explain the reason for this death.

Dear Student,


1. An accident is holding up traffic. 

2. I am surprised you fell for that trick.

3. The investigation team is at a loss to explain the reason for this death. 

Hope this answers your question.For further doubts, please ask on the forum and our experts will be happy to help. 

Regards.