51. begin to

　　52. begin doing

　　53. start to

　　54. start doing

　　55. cause/lead/enable/asce/order sb to do sth

　　56. attempt to do sth

　　57. expect sb to do sth; sb be expected to do sth; sb expect (it is expected) that +句子

　　58. be compared to/with

　　59. appear/seem to do

　　60. at a time when +句子