17. It is easy to think you understand another person,( ) later that you were wrong.

23. This drink is very tasty, and it is nutritious as well, as it is ( ) with vitamin C.

22. Your earnings will be in ( ) to the amount of work you do.

21. nn hurried back, having a guilty ( ) at leaving her daughter at home alone.

20.Firms that use computers have found that the number of staff ( ) is needed for quality control can be substantially reduced.

19."If you frequently forget where you parked your car, there is an app that (could) be what you're looking for." The underlined word expresses ( ).

18."It (is taking) forever to upload an album." The underlined part expresses ( ).

17.One can never be happy if one is always envious ( ) others.

16.My mother (would have been) in Beijing by now if she had not missed the train. The underlined part in the sentence expresses a(n) ( ).

15.If you (would) kindly agree to the terms, we'll send you the samples right away. The underlined word indicates ( ).

14.A more flexible means of communication is always an advantage, ( ) being equal.