Question

3. (2015江苏滨海陆集中学第二次月考，3. ★★☆) It is mean- ingful  children  in charity work at a young age.

   A. of;to join   B. for;to join

   C. of; joining   D. for;joining

Answer 1

3. B

3. B句意:孩子们在很小时参加慈善工作是有意义的。考査

句型 It is+aáy.+for sb. to do sth.。故选 B