VI.Use Present Perfect Simple or Present Perfect Progressive.I have (to diet) for the past few years. I have (to try) all sorts of diets. 2. I have (to take) dancing lessons since last year. I have (to learn) three dances. 3. I have (to study) English since I was 7. Now I can speak fluently. 4. – Oh, you look great! – Yes, I have (to ride) my bike for a month. 5. I have (to do) sports for two years. I have (to have) good results.​

1. I have been dieting for the past few years. I have tried all sorts of diets.

2. I have been taking dancing lessons since last year. I have learned three dances.

3. I have been studying English since I was 7. Now I can speak fluently.

4. – Oh, you look great! – Yes, I have been riding my bike for a month.

5. I have been doing sports for two years. I have had good results.

Объяснение:

1важно потому  что без хорошей экологии мы будем жить в грязи и дышать газом 2 тем что кислотные дожди разносятся ветром в другие страны и портят имущество 3 тем что леса из углекислого газа производят кислород и тогда кислорода будет меньше 4 тем что озоновый слой не пропускает солнечные лучи на землю ибо тогда  всё живое сгорело 5 тем что это повлияет на экологию,ведь охлаждение температуры ведь  искусственное вмешательство в природу опять же влияет на экологию 6 наш вид приспособился к нормальной температуре при которой и развилась жизнь.

"the baby boom" doesn't help: working hands is getting smaller demographic statistics in russia resembles the statistics of the war period: the population is shrinking every year 700 thousand people. mortality is twice that in developed countries, and life expectancy among men is the lowest in the world, 60 years. now if in the country of 142 million people, by 2050 there may remain only 100 million vladimir putin in 2000 indicated that the population decline threatens the very existence of russia. six years later he increased support for mothers and offered a premium for the birth of her second child. the birth rate began to rise, but the mortality rate has not declined, as did not increase lifespan. putin cheered and said that in the next three to four years the country will be able to stabilize the demographic situation. in fact, reasons for optimism are few, and to achieve this goal, increasing the population of the russian federation up to 145 million people, it is impossible, experts say. the head of the center for demography and human ecology anatoly vishnevsky says that one of the "baby boom" does not mean anything: it's possible that people decide to have children now, while this form of the prize, but in the long term the total number of children in families will not increase. the middle class will not tempt the cash payments. scientists attribute the current surge in the birth rate that matured and began to start families, many children of the 1980-ies. but the next generation of parents will be much fewer in number. "in the next few years we will see a sharp decline in the birth rate," warns wisniewski. at the same time, the mortality rate will rise - there will come a time to die post-war generation of children.