A communicative satellite ________________ as much as 3.5 tons was sent up into space last week. A. weighing B. weighed C, to be weighed D. being weighed
33. Some people skip meals or eat only tiny amounts of food and may have conditions ______ rob the body of the nutrients ______ needs to grow and stay healthy.
31. In the past few years, research has suggested that Vitamin D may increase the level of serotonin(血清素), one of the key neurotransmitters influencing our mood, and ________it helps to relieve mood disorders.