"After the books have been printed, they are then bound together."
Explanation: By using "after + present perfect," we can connect the two stages of the process to show the sequence of events. In this case, we are showing that the books are bound together only after they have been printed.
"Once the dough has been kneaded, it is then left to rise."
Explanation: Using "once + present perfect," we can show that the second stage of the process (in this case, letting the dough rise) only happens after the first stage (kneading the dough) has been completed.
"When the vegetables have been washed, they are then chopped into small pieces."
Explanation: By using "when + present perfect," we can show that the second stage of the process (chopping the vegetables) happens immediately after the first stage (washing the vegetables) is completed.
"After the cake has been baked in the oven, it is then decorated with frosting."
Explanation: Using "after + present perfect," we can show that the second stage of the process (decorating the cake) happens only after the first stage (baking the cake in the oven) has been completed.