seal做動(dòng)詞有密封;蓋印;明確等意思，那么你知道seal的過去式是什么嗎?下面是學(xué)習(xí)啦小編整理的seal的過去式和用法例句，希望對(duì)大家的學(xué)習(xí)有所幫助!

　　seal的過去式和其他時(shí)態(tài)：

　　過去式: sealed

　　過去分詞: sealed

　　現(xiàn)在分詞: sealing

　　seal的用法：

　　seal的用法1：seal用作名詞時(shí)的意思是“印章”,轉(zhuǎn)化為動(dòng)詞的意思是“蓋章于…上”,引申可表示“封”“封口”“封住”“最后確定”等。

　　seal的用法2：seal只用作及物動(dòng)詞,接名詞、代詞作賓語。

　　seal的過去式例句：

　　1. The areas are sealed off and ringed by troops.

　　這些地區(qū)被軍隊(duì)封鎖包圍了。

　　2. Helicopters with searchlights swept the park which was sealed off.

　　直升飛機(jī)的探照燈來回掃射這個(gè)被封鎖的公園。

　　3. Police and troops sealed off the area after the attack.

　　襲擊發(fā)生后警察和士兵將該區(qū)域封鎖。

　　4. A heavily armed guard of police have sealed off the city centre.

　　一隊(duì)全副武裝的警察已經(jīng)封鎖了市中心。

　　5. Make sure that your tiles are thoroughly grouted and sealed.

　　要確保這些瓷磚經(jīng)過徹底灌漿并且密封好。

　　6. A courier was despatched with two sealed envelopes.

　　信使受命遞送兩封封訖的信。

　　7. The milk was sterilized and sealed in bottles.

　　牛奶經(jīng)過滅菌處理后被封裝在瓶子里。

　　8. Windows are usually sealed off.

　　窗戶通常是封閉的。

　　9. The floor is sealed to prevent water penetration.

　　地板加了密封涂料防止?jié)B水。

　　10. We will never forget the friendship sealed in adversity.

　　患難之交永不忘.

　　11. The country sealed its borders to prevent the influx of illegal immigrants.

　　為了防止非法移民大量湧入,該國封閉了邊境.

　　12. We sealed our agreement by shaking hands.

　　我們最后以握手表示達(dá)成了協(xié)議.

　　13. She sealed the letter.

　　她把信封上了.

　　14. The arrival of reinforcements sealed our victory.

　　增援部隊(duì)的到來決定了我們的勝利.

　　15. The friendship sealed in adversity is the sincerest.

　　患難中結(jié)成的友誼最真摯.