Fill in the blank in the passage give verb given in brackets.
Breathing is good, on this we ______ (1) (can) agree. That is why sleep apnoea, a condition in which sufferes repeatedly ______ (2) (stop) breathing and _____ (3) (awake) during the night, _____ (4) (be) so distressing and dangerous. Doctors _____ (5) (have) long known that the majority of people with sleep apnoea also _____ (6) (have) gas and reflux, so they often ______ (7) (treat) the reflux with heartburn and medication. To prove the connection between reflux and sleep apnoea, scientists at an army hospital ____ (8) (observe) apnoea patients as they _____ (9) (sleep). They _____ (10) (find) that reflux could, in fact be the cause of many night-time awakenings.
