Make 4 sentences by using active sentence and change it into passive tolong dibantu yak

Tommo wrote a letter yesterday morning
A letter was written by Tommo yesterday morning

The Cops are trying to catch the robber.
The robber is being caught by the Cops.

 My mother cleans the kitchen once a week.
The kitchen is cleaned by my mother once a week.

Many tourists have visited that beach. 
That beach has been visited by many tourists