Поставьте глаголы в скобках в Present Perfect
или Past Simple.
1) These tasks … (have) many
difficulties.
2) … production managers … (analyse) these data
yesterday?
3) A constructor … (build) a house.
4) They … (investigate) the problem a week ago.
5) Inflation … (affect) on the economy a lot.
6) Early settlers … (preserve)
meat by drying and salting it.
7) They … (just/elect) the president of the company.
8) The children … (skate) on the frozen pond last
winter.
9) The department … (already/mail) out 200 notices.
10) When he … (return) home they … (not/be) ready.
11) The Olympic committee … (announce) the results.
12) We …(be) here since ten o'clock.