Хм.
Объяснение:
Tom is writing a letter at the moment.
Alice was watching a TV programme at 7 o'clock this morning.
You has been working hard today.
Sue was working hard yesterday while Nick was playing computer games.
Are they walking to school now?
Kate wasn't coming to school on Tuesday at half past four in the afternoon.
Paul was cleaning up his room this evening.
Were they walking to school when we saw them?
