Final answer:
The sentence "I'm going to my cousin's house this weekend." is declarative.
Step-by-step explanation:
The sentence "I'm going to my cousin's house this weekend." is declarative.
A declarative sentence makes a statement or expresses an idea. It ends with a period. In this example, the sentence is stating that the person is going to their cousin's house over the weekend.
The subject of this question is English because it relates to the study and understanding of sentence types in the English language.