3 sentences

1. 他埋头在风雨中赶路。

   tā mái​tóu zài fēng​yǔ zhōng gǎn​lù.

   He trudged through the wind and rain with his head down.

   Source: Dong Chinese Dictionary

2. 他最近正埋头准备研究生考试。

   tā zuì​jìn zhèng mái​tóu zhǔn​bèi yán​jiū​shēng kǎo​shì.

   He has been immersing himself in preparing for the postgraduate entrance exam lately.

   Source: Dong Chinese Dictionary

3. 这种家具装配需要使用埋头螺钉。

   zhè zhǒng jiā​jù zhuāng​pèi xū​yào shǐ​yòng mái​tóu luó​dīng.

   This furniture assembly requires the use of countersunk screws.

   Source: Dong Chinese Dictionary