350. by guess 靠猜

349. guess at 猜, 估计

348. guard against (=defend, keep safe)警惕,防止 guard…against 警卫…防止

347. on one’s guard(against) 谨防, 警惕 (be) on guard 站岗

346. fall to the ground (计划.希望等)失败,落空

345. on the ground(s) fo (=because of) 由于…

344. be grateful to sb. for sth 因…感谢某人

343. take…for granted (=assume to be true)把…认为理所当然的.

342. for good (=for ever) 永远地, 长期地

341. in good time(=early)早早地(做完.到达等)