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50. After they had got ready, they went out to dinner. ( After+ quá khứ hoàn thành, quá khứ đơn.)
51. After she had explained everything clearly, we started to work. ( After+ quá khứ hoàn thành, quá khứ đơn.)
52. After David had gone home, he watched TV with his mother. ( After+ quá khứ hoàn thành, quá khứ đơn.)
53. John congratulated us on having passed the final exam. ( congratulate sb on doing sth: chúc mừng ai về việc gì.)
54. The teacher accused him of having not paid attention to what she had said. ( accused sb of doing sth: buộc tội ai đó về việc gì.)
55. Mike thanked me for inviting her to my birthday party. ( thank sb for doing sth: cảm ơn ai về việc gì.)