giải giúp mk với ạ please

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1. My English speaking skill has been improved dramatically over the last three years.
2. The number of unemployed graduates has increased slightly this year.
3. There has been a gradual rise in the number of Vietnamese students studying in the U.S.
4. The economy has grown considerably this year.
5. There has been a rapid decrease in the number of foreign tourists to Vietnam during the past years.
6. Our coffee exports failed significantly due to bad weather.
7. The price of computers will decrease steadily.
8. There has been a dramatic change in the traffic system in Vietnam in recent years.