1: \(2155-\left(174+2155\right)+\left(-68+174\right)\)

=2155-174-2155-68+174

=(2155-2155)+(174-174)-68

=-68

2: \(-25\cdot72+25\cdot21-49\cdot25\)

\(=25\left(-72+21-49\right)\)

\(=25\cdot\left(-100\right)=-2500\)

3: \(35\left(14-23\right)-23\left(14-35\right)\)

\(=35\cdot14-35\cdot23-23\cdot14+23\cdot35\)

\(=35\cdot14-23\cdot14=12\cdot14=168\)

4: \(8154-\left(674+8154\right)+\left(-98+674\right)\)

=8154-674-8154-98+674

=(8154-8154)+(674-674)-98

=0+0-98

=-98

5: \(-25\cdot21+25\cdot72+49\cdot25\)

\(=25\left(-21+72+49\right)\)

\(=25\cdot100=2500\)

6: \(27\left(13-16\right)-16\left(13-27\right)\)

\(=27\cdot13-27\cdot16-16\cdot13+16\cdot27\)

\(=27\cdot13-16\cdot13=11\cdot13=143\)

7: -1911-(1234-1911)

=-1911-1234+1911

=-1234

8: \(156\cdot72+28\cdot156\)

\(=156\cdot\left(72+28\right)\)

\(=156\cdot100=15600\)

9: \(32\cdot\left(-39\right)+16\cdot\left(-22\right)\)

\(=16\cdot\left(-78\right)+16\cdot\left(-22\right)\)

\(=16\cdot\left(-78-22\right)=16\cdot\left(-100\right)=-1600\)

10: -1945-(567-1945)

=-1945-567+1945

=-567

11: \(184\cdot33+67\cdot184\)

\(=184\cdot\left(33+67\right)\)

\(=184\cdot100=18400\)

12: \(44\cdot\left(-36\right)+22\cdot\left(-28\right)\)

\(=22\cdot\left(-72\right)+22\cdot\left(-28\right)\)

\(=22\cdot\left(-72-28\right)=22\cdot\left(-100\right)=-2200\)

9.      She dislikes talking to strangers.

10.  This camera was bought 2 days ago.

11.  Lan is both clever and beautiful.

12.  Unless you phone her, she will be very sad.

13.  They are independent. (self-reliant/self-sufficient)

14.  Do you mind arranging flowers?

28. richness

29. unpopular

30. popularity

31. unpopularity

32. limitations

33. excited

34. further

35. familiarize

36. Originally

37. confusing

38. confusion

39. reducing

40. extremely

41. environmentalists

Rewrite sentences.

1.      I’m not as tall or intelligent as he is.

2.      I’ve never met a more intelligent girl than she is.

3.      We were made to do a lot of things.

4.      She is thought to be the richest woman in this city.

5.      Lan advised me that I should contact her more often.

6.      It’s the first time I’ve met her parents.

7.      This flat is not big enough for her family to live in.

This question can't be answered

It is boring to stay in the same place so long

A lot of souvenirs were bought when they were on holiday

This house is too expensive for us to buy

Who does this house belong to?

I apologize for being rude to you yesterday