3 sentences

1. 请关好门，待在外面。

   qǐng guān​hǎo mén, dāi zài wài​miàn.

   Please close the door and stay outside.

   Source: OpenSubtitles

2. 离开房间时请关好门窗，注意防盗。

   lí​kāi fáng​jiān shí qǐng guān​hǎo mén​chuāng, zhù​yì fáng​dào.

   Please close the windows and doors when leaving the room and watch out for theft.

   Source: Dong Chinese Dictionary

3. 请你在离开办公室之前记得把所有的窗户和门都关好。

   qǐng nǐ zài lí​kāi bàn​gōng​shì zhī​qián jì​de bǎ suǒ​yǒu de chuāng​hu hé mén dōu guān​hǎo.

   Please remember to close all the windows and doors properly before you leave the office.

   Source: Dong Chinese Dictionary