after thought & second thought 不是原計劃內與不同意見

After thought - not original planed

The parents said that the baby was an after thought. 父母說生這個嬰兒不是原來計劃之內的。

Second thought - think it over , may change mind. 

Let me have a second thought. 容我再考慮一下！

 

Second opinion: He would like to have a second opinion from another doctor.  他要聽聽另一個醫生的不同意見！