She has a perm. (She has a permanent wave. -- Is this the full form?)

Question

She has a polka dot dress.
The girl has pigtails /braids/ plaits. (What is the difference between the three?)
Her older sister is wearing a pink plain dress.
Her brother is wearing a horizontally striped sweater.
She is wearing a vertically orange plain skirt.
The girl is wearing a ribbon on top of her hair.
The girl having a pony tail is wearing a patterned dress.
The wife is wearing a pink polka dot dress.
Her mother has a long wavy black hair.
-------------------
Are the expressions all correct? Would you check them?

Answer 1

She has a perm. (She has a permanent wave. -- Is this the full form?) "perm" is the common term; "permanent wave" is the full term but almost no one uses it.

She has a polka dot dress. OK

The girl has pigtails /braids/ plaits. (What is the difference between the three?) These are just different terms for the same thing; "braids" is most commonly used.

Her older sister is wearing a plain pink dress. do you mean "plain" or "plaid"?

Her brother is wearing a horizontally striped sweater. "horizontally" is not usually mentioned

She is wearing a vertically orange plain skirt. delete "vertically" - and do you mean "plain" or "plaid"?

The girl is wearing a ribbon in her hair.

The girl with a pony tail is wearing a patterned dress.

The wife is wearing a pink polka dot dress. OK

Her mother has a<~~delete "a" long wavy black hair. add commas after "long" and "wavy"

Answer 2

Thank you. I mean 'plain' without having colored or patterned shape on the clothing. Is 'plain' commonly used?

Answer 3

Not usually. If there's no plaid or check or pattern or stripe, it's usually not even mentioned.

Answer 4

Braids can be one or more plaited strands of hair and can be wound around the head or worn any way.
Pig tails are usually on small girls and consist of two braids, one hanging down on each side of the head, and they usually have a ribbon tied around the end.