51. The horse won’t be well enough (run) in tomorrow’s race. He doesn’t seem (have) recovered from his long journey. 52. At first I enjoyed (listen) to him but after a while I got tired of (hear) the same story again and again. 53. It is usually easier (learn) a subject by (read) books than by (listen) to lectures. 54. It wouldn’t be safe (start) down now; we will have (wait) till the mist clears. 55. After (discuss) the matter for an hour the committee adjourned without (have) reached any decision. 56. It’s not much use (have) a bike if you don’t know how (use) it. 57. I distinctly remember (pay) him. I gave him 2$. 58. Did you remember (give) him the key of the safe? - No, I didn’t. I will go and do it now. 59. Please forgive me for (interrupt) you but would you mind (repeat) that last sentence. 60. He made a lot of money by (buy) tickets in advance and (sell) them twice the price on the day of the match. mn giúp em với ạ!!

51. The horse won’t be well enough (run) to run in tomorrow’s race. He doesn’t seem (have) to have recovered from his long journey. ( enough to V , seem to V )

52. At first I enjoyed (listen) listening to him but after a while I got tired of (hear) to hear the same story again and again.

53. It is usually easier (learn) to learn  a subject by (read) reading books than by (listen) listening to lectures. ( It is easy to do something: thật dễ dàng để làm một việc gì đó , Sau by + V - ing )

54. It wouldn’t be safe (start) to start down now; we will have (wait) to wait till the mist clears. (  "be safe to V": an toàn để làm gì.,  "have to V": phải làm gì. )

55. After (discuss) discussing  the matter for an hour the committee adjourned without (have) having  reached any decision.

56. It’s not much use (have) a bike if you don’t know how (use) to use it. ( How to V )

57. I distinctly remember (pay) paying him. I gave him 2$. ( remember Ving )

58. Did you remember (give) giving him the key of the safe? - No, I didn’t. I will go and do it now. (  remember Ving )

59. Please forgive me for (interrupt) interruptin you but would you mind (repeat) repeating that last sentence.

60. He made a lot of money by (buy) buying tickets in advance and (sell)  selling them twice the price on the day of the match.

Cho mìn xin ctlhn nha!

@Bảo Ngọc