连词成句。

1. to   I   sing   love

                                                 .

2. always   I   sing   to   like

                                                 .

3. can   Jenny   piano   the   play

                                                  .

4. want   I   sing   everyone   to   loudly

                                                  .

5. likes   sing   Who   to

                                                   .

简述反致产生的原因与条件。