a The two climbers stopped to rest. They had been climbing for hours and were exhausted. Things were not looking good.
b They were very cold, because it (had been snowing) heavily since mid-
morning, and one of them (had hurt) his ankle.
c They (had been looking) for shelter for the past two hours, because they realized that the weather was going to get worse.
d They (had already phoned) the rescue centre for help.
e They (had also left) details of their planned route at the village where they
slayed the night.