(토플) Life expectancy had improved steadily over the years, (_____) deaths during childhood.
1) due to large a decline in
2) largely a decline in due to
3) largely due to a decline in
4) largely in due to a decline
(토플) Although (_____), skin is often viewed as simply a barrier between the body and the outside world.
1) a part of the immune system
2) there is a part of the immune system
3) it is the part of a immune system
4) the immune system is a part of it
