sister
The word 'soeur' corresponds to the English word 'sister'. In French, it is used in the context of family connections. Just like in English, it refers to a female sibling. It is also used in religious context to refer to a nun.
Laura's sister is an artist.
This sentence uses 'soeur' to define the professional status of Laura's sister. In this case, she is an artist.
My sister and I are going to school.
This is a simple sentence showing the use of 'soeur' in a straightforward context, meaning 'sister'. The speaker is indicating that both she/he and their sister are heading to school.
Pierre's sister is very tall.
In this sentence, 'soeur' is used in the context of possession, indicating the sister of Pierre. This sentence is talking about the physical attribute (height) of Pierre's sister.
My sister loves dogs.
This sentence uses 'soeur' to indicate a preference or like of the speaker's sister. The sister likes dogs.
I'm going to my sister's house tonight.
In this example, 'soeur' is used to describe a destination. The speaker plans to visit his/her sister's place.
My sister's mother is my teacher.
This sentence has a little complexity as it links familial relationships with professional roles, but its meaning is quite literal. The speaker's sister's mother is also the speaker's teacher.
I cannot speak because my sister is sleeping.
Here, 'soeur' is used in a causal relationship. The speaker can't speak because the action would disturb their sleeping sister.
My friend's sister works in Spain.
In this example, 'soeur' is used to describe a tertiary relationship (friend's sister) and provide information about her location of work.
My father has only one sister.
This sentence talks about the speaker's family structure. In this context, 'soeur' is used to indicate the number of sisters the speaker's father has.
My sister and I have the same birthday.
In this sentence, 'soeur' is used to express a shared characteristic between the speaker and his/her sister - they both have the same birthday.