Meaning of dǔ:
堵
to block up (a road, pipe etc); to stop up (a hole)
Mǎlù shàng de jiāotōng dǔ le.
马路上的交通堵了。
The traffic on the road is blocked.
Zhège xiàshuǐdào bèi shùyè dǔ zhù le.
这个下水道被树叶堵住了。
This drain is clogged by leaves.
(fig.) (of a person) choked up with anxiety or stress
Tā xīnlǐ gǎndào fēicháng dǔ.
他心里感到非常堵。
He felt very choked up with anxiety.
wall (literary)
Zhè miàn qiáng yǐjīng bèi fēngyǔ qīnshí chéng yī dǔ jiù qiáng.
这面墙已经被风雨侵蚀成一堵旧墙。
This wall has been eroded by wind and rain into an old wall.
(classifier for walls)
Nà shì yī dǔ gāogāo de qiáng.
那是一堵高高的墙。
That is a tall wall.