Chia động từ trong ngoặc sao cho phù hợp. 1. If you (send) _________________ this letter now, she (receive) __________________ it on next Monday. 2. I will pass my final test if I (work) __________________ hard. 3. She (go) __________________ camping if she (have) __________________ free time, but she's very busy now. 4. If people (continue) _____________ to cut down trees, they (cause) ______________ a lot of damage to the environment. 5. If I (be) __________________ 17 again, I (spend) __________________ more time reading books. 6. If you (want) __________________ to go scuba-diving, you (need) __________________ breathing equipment. 7. If he (have) __________________ enough money, he (go) __________________ on an eco tour to Phong Nha national park, but now he's on a tight budget.