1. "My father often **go** to work on Fridays."
صحیح: "My father often **goes** to work on Fridays."
2. "We usually **goes** out for lunch on Fridays."
صحیح: "We usually **go** out for lunch on Fridays."
3. "we go to my grandfather **house**."
صحیح: "we go to my grandfather's **house**."
4. "My grandfather **are** very kind."
صحیح: "My grandfather **is** very kind."