forEach do multiple commands

I have a code in my rule like this:

gShutter.members.forEach[ i | i.sendCommand("DOWN")]

I need to replace it with one, that sends command DOWN and then waits for 1 sec before sending another command DOWN for the other member. I tried this:

gShutter.members.forEach[ i | i.sendCommand("DOWN") && Thread::sleep(1000)]

But this results in:

org.eclipse.smarthome.model.script.engine.ScriptExecutionException: Unknown variable or command '&&'; line 161, column 38, length 44

Can you help please?

Just put ordinary code to do that inside the [ ]