Task 2. Complete the question tags. Follow and check the points at first:
- what tense is the verb?
- what kind of verb is it (be, modal, other)?
- is the sentence affirmative or negative?
- does the pronoun need to be changed?
Example
You went to see the doctor, didn't you?
You play snowballs every winter, ?
They weren’t doing their homework yesterday after supper, ?
Money isn't everything, ?
Computers are very useful, ?
Life was better 100 years ago, ?
We can all make mistakes, ?
Parents shouldn't hit their children, ?
Students must do their homework, ?​

Kostomukshsky Reserve.
In December 1983 was created Kostomukshsky Reserve. Clear natural boundary of the reserve has not. The western boundary runs parallel to the border with Finland, a few kilometers away, and the south-west - the coast of the lake. Stone. Southern, eastern and northern boundaries of the reserve are held quarterly vizier.
Bashkir reserveBashkir State Nature Reserve is located in the Republic of Bashkortostan, on the spur of the Southern Urals. The reserve was established July 11, 1930. In 1951, the decision of the Council of Ministers of the Bashkir ASSR Reserve was liquidated and its territory is organized forestry: began intensive exploitation of the forest. Only in November 1958, the first reserve Bashkiria has been restored.
State Wrangel Island Reserve.Far above the Arctic Circle is the most easterly Reserve Russia - Wrangel Island. Its area is 795,650 hectares. But the reserve is not only Wrangel Island, but the island Herald.

1) They have just returned from their holiday.
2) They have stayed in New York for a week.
3) The Browns have moved into their new house.
4) They have sold the old one two weeks ago.
5) She has bought an expensive dress.
6) She has bought it yesterday.
7) John has taken his car to the garage.
8) Я не поняла.
9) Mrs Gate hasn't tidied her house yet.
10) She has gone for a walk.
11) She has leaved about two hours ago and 12)hasn't come back yet.
13) Mr Moore has already cut the grass but he 14) hasn't painted the fence yet.