Children __________swim in the river without adults(成年人).

The mountain village is so beautiful.-Yes.Moreover，________the villagers live，there is fresh air.[ ]

The teacher finally ________ his project to the school board for approval.[ ]

Hurry up﹗The train ______. You know it ______ at 9:00 am.

n’t want to see anybody, so he spent six hours ________ in the small room