"You must keep your promise," said the little prince, softly, as he sat down beside me __________.
__ carefully if any change occurs when doing experiments in the lab..
Jane is in a hurry because the train to the airport leaves _______ half an hour.
---Hi, let’s go skating. --- Sorry, I’m busy right now. I _______ in an application form for a new job.
Some animals carry seeds from one place to another,plants can spread to new places.
— I get at least half an hour of exercise almost every day.— Oh great! .