if we take short breaks__.19. Food in small pieces could be eaten easily from the sun twigs which_ turned into chopsticks.20. Walls make of adobe take in the heat from the sun on hot days and give out that heat_ during cool nights， thus warning the house.21. …
500 outside [ˈautˈsaid] prep./ n./ ad./ a.(在，向)的外面(的)501 piece [pi:s] n.片，块，段，件；断片，碎块 vt.拼合(凑)502 sometimes [ˈsʌmtaimz] ad.
【重点词组】1. invite sb. to do sth.邀请某人做某事2.one of +形容词最高级+ 名词复数3. say thanks/hello/sorry/good-bye to sb.向某人致谢/问好/道歉/告别4.
