40 )They have built the bridge for two years

41 ). Nam has learnt English since 1998

42  ). Bang has raised birds since May

43 )  Van has collected stamps since Sunday

44 )  Van has listened to music since 8 o'clock

45 ) Mai has made a dress since Saturday

46 ) He has watered the vegetables since nice

47 )  Khanh has played computer games since 2002

48 ) Kim has done the test since one o'clock

49 )  Miss Lien has raised the pets since 2010

50 )  Minh has sold lottery tickets since June

40. They started building the bridge two years ago

⇒ They have built the bridge for two years

41. Nam started learning English in 1998

⇒ Nam has learnt English since 1998 

42. Bang began raising birds in May

⇒ Bang has raised birds since May

43. Van started collecting stamps on Sunday

⇒ Van has collected stamps since Sunday

44. Hang began listening to music at 8 o'clock

⇒ Hang has listened to music since 8 o'clock

45. Mai commenced making a dress on Saturday

⇒ Mai has commenced making a dress since Saturday

46. He began watering the vegetables at nine

⇒ He has watering the vegetables since nine

47. Khanh started playing computer games in 2002

⇒ Khanh has played computer games since 2002

48. Kim commenced doing the test at one o'clock

⇒ Kim has commenced doing the test since one o’clock

49. Miss Lien commenced raising the pets in 2010

⇒ Miss Lien has commenced raising the pets since 2010

50. Minh began selling lottery tickets in June

⇒ Minh has sold lottery tickets since June