It takes sb.time to do sth. It took us a long time to build the house. It is n.to do sth. It is It is fun /no use junk no good doing .. pleasure/honour/duty/good idea... It is important for It is adi for sb.to do sth us to learn English. 重难必安危：important,.difficult/,hard/easy,necessary, safe,dangerous... tiso@】 to do sth. It is kind of you to help me. 勇明笨善礼：brave,clever/smart,silly/stupid/foolish,kind,polite..It took us a long time to build the house. 3 4 1 It takes sb. time to do sth. It is n. to do sth. It is adj. for sb. to do sth. It is adj. of sb. to do sth. It is not a good idea to eat junk food. It is important for us to learn English. It is kind of you to help me. 2 pleasure/honour/duty/good idea... 勇明笨善礼：brave, clever/smart, silly/stupid/foolish, kind, polite... 重难必安危：important, difficult/hard/easy, necessary, safe, dangerous... It is + fun /no use / no good + doing … it→ to do