1. when(1) When I ________________(到达机场), the guests had left.   When they heard the news, they jumped with joy.   = When __________ the news, they jumped with joy.   = While ____________ the news, they jumped with joy.   When the medicine is taken with water, it works better.  = When/ while _______ with water, it works better.(2) I was about to go out _____ it began to rain.  They were watching TV _____ suddenly the lights went out.  We had just settled down _____someone knocked at the door.2.  ...