Điền vào chỗ trống bằng những liên từ thích hợp 1. I'll come and see you _____ I leave for Moscow. 2. He will tell you _____ you get home. 3. I can't express my opinion _____ I know the fact. 4. We started very early _____ we should miss the train. 5. He will stay here _____ you come. 6. _____ he tried hard, he wasn't successful.