Dr. Anne Yue-Hashimoto pointed out that tone change in Taishanese is a mark of the colloquial language. Tone change transformation produced the following commonly used prepositions of location.

门前 [mɔn22 tein22] front of the door -> [mɔn32 tein21] front
尾门 [mi55 mɔn225] back door -> [mi55 mɔn21] back
后背 [hǝu32 bɔi33] back of body -> [hǝu32 bɔi21] back
耳后 [ŋi55 hǝu32] behind the ear -> [ŋɛ55 hǝu21] behind
瓦下 [ ŋa55 ha32] under the roof -> [ŋa55 ha21] below
侧身 [dzak55 sin33] to turn one's body -> [dzak55 sin21] side
隔篱 [gak33 li22] separated by a bamboo fence -> [gak33 li21] next, near
转曲 [dzɔn55 kǝk55] to turn/twist -> [dzɔn55 kǝk21] around the corner

Note that the trailing syllable tones were all changed to the low-falling (21), which is the tone for many of the most familiar colloquial terms. This type of transformation reminds me of the country and folksy roots of the language.