英语试卷中对介词的考查往往是以考查含有介词英语词组的形式出现的，例如:be good at /be interested in/ be short of 等，也要注意对with/without/to/for的考查。
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. …
