Nuclear energy may be dangerous if
They were surprised that a child could work out the problem ______ they themselves couldn’t.
--- I hear Jane has gone to the Holy Island for her holiday. --- Oh, how nice! Do you know when she ______ ?
The factory was built in a secret place, around _____ were high mountains.
The teachers were discussing the research project that they would like to see _____ in the coming holiday.
--- It’s the office! So you ______ know smoking is not allowed here. --- Oh, sorry.