填空题

It’’s never too early to (36) ________your skin-or your children’’s-from the sun. The sun produces (37)________ rays- (38) ________ A (UVA. and (39)_________B (UVB. -that can cause short-and long-term skin damage. The immediate effects of harmful (40) ________- (41) ________, photosensitive (42) ________, and cell and (43) ________damage-are bad enough. But medical experts believe that (44)___________________________.Health experts also believe that UVA may weaken the immune system. (45)___________________________.Using sunscreens regularly on children, for example, can reduce their risk of skin damage later in life. Sunscreens provide some protection by blocking the sun’’s rays on the skin. (46)___________________________. But no sunscreen totally blocks the sun’’s rays.