4. 有些国家有丰富的石油，而有些国家却一点儿也没有。Some countries are rich in oil, ______ some countries have none.
举一反三
- Some countries are _______(丰富的石油)， while some countries have none.
- 有些国家有丰富的石油，而有些国家却一点儿也没有。（...while...)
- Some countries are _______(丰富的石油)， while some countries don't have any.
- The news report says children in some countries have no money to buy watches.
- Developed countries， like the US， have moved the some manufactures to the developing countries. Is it true or not? （）