http://chanyi.new21.net/zbxe/64979
18. help의 목적어와 목적보어
Point
동사 help 뒤에 오는 동사는 형태가 to부정사나 원형부정사 둘 다 될 수 있으며 ‘~가 ~하는 것을  돕다’라는 뜻이다

help (목적어) + (to) 동사원형 : 도움을  주다
help + -ing : 피하다

Practice
․ Ocean coral will surely play a major role in helping doctors [repairing / to repair] bone fractures.

․ Beyond [their / its] nutritional benefits for babies and adults, milk also contains acids that  help the body [to sleep / sleeping] more easily.

․ Scientists study pairs of identical twins who grew up in different surroundings. These twins help scientists [understand / understanding] the connection between environment and biology.