用作定语
▲～+n.
 My desire for a desirable house will come true in the near future.我要买一幢称心如意的房子的愿望在不久的将来将会实现。
用作表语
▲S+be+～
 Some reasonable adjustments seem desirable.某些合理的调整似乎是可取的。
▲It is/was+～+to-v
 For this job it is desirable to know something about medicine.做这项工作最好能懂点医学。
▲It is/was+～+that-clause
It is most desirable that your parents should both go.你父母都去,那最好不过了。