which of these sentences have paticipial constructions?

1. The eventual launch of a Social Democratic Party, possibly with Mrs. W. as a leader, is one tactic being seriously considered.
2. Mexico City – Having long considered a strong military unnecessary, Mexico suddenly decided to spend a portion of its oil earnings on armaments – and for the first intended to buy supersonic jet fighters in the United States.
3. While seeing the danger it is also essential to confront the pessimism created by a section of the mass media.
4. They wanted a Government freely chosen by the will of the people.
5. We will not seek to frustrate the consensus, since it is not in the world interest to have the work of the General Assembly immobilized in those troubled days.
6. The bureaucratic management remained the directors and managers of the new nationalized industries, with a few right-wing trade-union officials thrown in for luck.
7. General strike spirit began to run like wildfire, one local union after another endorsing the proposal of a complete tie-up.
8. A Ju 88 was short down by our fighters, the crew being taken prisoner.
9. Being remarkably fine and agreeable in their manners, Oliver thought them very nice girls indeed.
10. The peaceful demonstration at the big Ford plant in the Dearborn was broken up, with four workers killed and fifty wounded.
11. After making this statement the minister said he was not going to consider his decision.
12. Besides being extremely unpopular this policy may lead to a complete failure of all their efforts.
13. Far from being a triumph, it was the biggest surrender in modern diplomacy.
14. The Government has acted to improve work incentives by reducing corporate and personal income tax rates, and by increasing share ownership among employees.
15. The countries financial difficulties being unsolved undermine its economic stability.
16. And I am sure no one doubts your being at liberty to do whatever you like.
17. They established it without waiting for an international treaty to be concluded, as prices at the London Stock Exchange began their climbing up.
18. It is nonsense for its supporters to claim that the present policy is a success. It has succeeded in increasing the number out of work, and in reducing production.
19. By not losing sight of the long-term objectives they made themselves masters and not servants or victims of economic forces operating in the world.
20. Mr. N. in a comment last night said the Government was making “a grave mistake in not taking the opportunity of explaining their policy to the country and submitting it to public criticism and comment”.

help me please!!