What is the meaning of 要 in these sentences? While doing exercises on my book I found some sentences with a use of 要 which I've never seen before and I can't figure out the meaning. The sentences are the following:

他很忙，但是他应该要来参加我的生日晚会
要实现梦想不是一件容易的事 and 要把汉语学好不是一件容易的事
All three examples can be interpreted as a future auxiliary.


  他很忙，但是他「應該要」來參加我的生日晚會
  
  He is very busy, but he「should be」coming to my evening birthday party.


This「要」is used in the sense of will, going to, like 我明天要上學 (I will be going to school tomorrow). Similarly,


  要實現夢想不是一件容易的事
  
  To realise (one's) dreams is not an easy matter
  
  要把漢語學好不是一件容易的事
  
  To learn Chinese well is not an easy matter