* Eu já cheguei no trabalho I've just arrived at work Yes, this is fine. * Estou descendo do ônibus This should be "I'm getting off the bus". The opposite is "I'm getting on the bus". NB We say 'getting on' and 'getting off' for large things such as buses, trains, boats and planes, and also for two-wheeled vehicles like bikes, and animals like horses. For smaller vehicles, such as cars, vans, trucks and taxis, we say 'getting in/getting into' and 'getting out of'.