If i..(have) a big house,i would invite all my classmates to spend their weekend

Jawaban:

If i had (have) a big house,i would invite all my classmates to spend their weekend

jawaban: Had

Penjelasan:

menggunakan past tense karena jika ingin dia ingin mengundang teman-teman sekelasya ke rumah dia, dia harus sudah punya rumah sebelum itu terjadi.